Ballistic Protection standards reference

[Blink_Dog]

Here is a chart that lists a whole bunch of different ballistic protection levels and standards.

http://www.nationwidestructures.com/ballistic-key.html

Keep in mind the 1st and 2nd editions did not include hard armour plate vests. PASGT is roughly equivalent to NIJ IIIa (most pistol rounds).

[Silent Hunter UK]

When was hard plate armour first fielded?

[Rockwolf66]

When was hard plate armour first fielded?

I've heard of a Hard Corps body armor from back in the 90's that was supposedly level 4. Alas I cannot find anything on the Net About it.

[Legbreaker]

When was hard plate armour first fielded?

https://en.wikipedia.org/wiki/Armour#History
A few millennia ago.

[ArmySGT.]

PASGT is roughly equivalent to NIJ IIIa (most pistol rounds).

Less...... NIJ II....... an anemic 9mm or .38.

These are fragmentation vests, not bullet resistant. IBAs have a higher rating.

[ArmySGT.]

When was hard plate armour first fielded?
American Revolution..... U.S. Navy..... some thought to helmets and breast plates for boarding party actions....... because who doesn't want 40+pounds of metal strapped to their torso while crossing a rope or ladder to an enemy vessel.

American Civil War....... Breast plates available by mail order catalog..... briefly considered, but not widely purchased for Cavalry.

WW1 Trench armor....... Breast plates........ fashionable and as effective as fog.

WW2 bomber waist gunners got something with metal plates...... since they didn't have to walk about......... I know of no anecdotal evidence or another kind.

Viet Nam..... Door gunners had a vest with overlapping plates. Again no evidence I am aware of..... Except that it was more effective sat on ........ to catch rounds coming up through the floor..... (more likely). Ummmmm "Chickenhawk" the autobiography may be where I am referencing this.

Mogadishu...... 1993...... 75th Ranger elements deployed with hard armor...... "Ranger Armor" because anything associated with Rangers must have Ranger in the title...... cannot reduce the cool factor by carelessly leaving that out.

Balkans...... 1998. ....... rumor mill is certain some units given Class IV police style SWAT vests........ no one of course had a camera.

Operation Clusterfu......... Iraqi Freedom......... Lottery.... some units have Interceptor body armor with plates......Some have Interceptor Body Armor (IBA)........... priority to Combat Arms in direct contact..... Most units.... including yours truly deployed with PASGT and received used and turned in IBAs with plates after eight months in country in counter ambush/counter IED patrolling or convoy escorts.

Ironically, U.S. National Guard.... funded differently and deployed differently were more likely to have IBAs with plates, PVS-14s instead of PVS-7bs, and next gen (smaller by half) SINCGARS.

[swaghauler]

There were three hard body armors available to US forces in the 1990's.

1. Ranger Body Armor: This body armor became available in 1993 and was made in TWO distinct versions. The first version is available with a plate made of 80% Aluminum Oxide and a special ceramic coating. This plate was 12" high by 10" wide and 3/8" thick providing an effective 70% (1-14 or less on 1D20) coverage of the chest (but no abdominal coverage). There is NO BACK PROTECTION IN FIRST GENERATION RANGER BODY ARMOR. This first version weighed 7.5 kilograms and 2000 were made.
The second version came out a year later and had BOTH front AND back plates providing the same general protection as the first generation had. The weight of this newer armor was 11.4 kilograms and about 4000 were made. Both generations of plate were rated at NIJ Level3 (rifle)/SAPI protection.

2. Interim Small Arms Protective Over-Vest: This protective overlay became available in 1996. This armor consisted of two Ceramic plates (NIJ Level 3 rifle/SAPI) which were designed to overlay either the PASGT vest or Ranger Body Armor. The plates provided 70% coverage (just like the Ranger Plates) to front and back and weighed 7.5 Kilograms (in addition to the PASGT or Ranger Armor). There were 4000 of these vests ordered by the Army as a "stop-gap measure" until better armors could be developed.

3. Interceptor Body Armor: This vest was developed in 1998 and originally came with two distinct sets of panels. The first set of panels are THREE (two front and one back) NIJ Level 3A (pistol) and provided better coverage of the vital organs (80% or 16 or less on 1D20). The vest weighs 3.8 kilograms with this basic protection in place. There are also TWO SAPI (NIJ Level 3 rifle) plates providing an improved 75% coverage (15 or less on 1D20) over the previous Ranger Plates. These plates fit into front and back pockets and provide added coverage to the basic NIJ Level 3A plates for just 1.8 kilograms per plate.

For those who are interested, the NIJ Armor Standards Are:

NIJ Level 1 is proof against 95gr .380 ACP at a Velocity of 1055 ft/sec.
NIJ Level 2A is proof against all previous threats and 124gr 9mmP at a velocity of 1225 ft/sec. This armor will also protect against 230gr .45ACP at 900 ft/sec, and 180gr .40 S&W at 1155 ft/sec.
NIJ Level 2 is proof against all prior threats plus; 124gr 9mmP at 1305 ft/sec and 158gr .357 Magnum at 1430 ft/sec. It will stop 12 gauge 00 Buck as well
NIJ Level 3A is proof against all of the prior threats plus; 125gr .357SIG at 1470 ft/sec and 240gr .44 Magnum at 1430 ft/sec. It will also stop 12 gauge slugs too.
NIJ Level 3 (rifle) will stop everything up to 147gr 7.62mm NATO FMJ at 2780 ft/sec. This is comparable to the Army's SAPI Standard. However, it has been penetrated by rounds exceeding 3000 feet per second, though.
NIJ Level 4 (rifle) This will stop everything up to THREE ROUNDS of 166gr .30-06 M2 AP at 2780 ft/sec. This armor is roughly equal to the Army's ESAPI plates.

The other standards that should be looked at are the new Russian GOST-R 50744-95 Standards, SchutzKlasse 2008 Standards, and HOSD Standards.

[swaghauler]

The primary armor for soldiers in the Twilight2000 era would have been the PASGT Armor with surplus Vietnam-era US Army M69 Flak Vests (3.5kg AV 1/2?) and the occasional M1955 USMC Vest (4.5kg AV 1/2?) as well.

PASGT Armor: This vest was introduced in 1985. It is NIJ Level 3A protection covering the chest (80%, 16 or less on 1D20) and the Abdomen (60%, 12 or less on 1D20) weighing 4kg for a medium size. It soldiered on into the 21st Century.

The only other "hard" armor that might be available in the Twilight2000 timeline would be surplus versions of the US Army's "Chicken Plate" Ballistic Armor for Helicopter Crews.

Aircrew Personal Body Armor: Made in 1968, it was the predecessor of the Army's Ranger Body Armor plates. Made primarily from 80% Aluminum Oxide and Ceramic, the plates came in two configurations. A single plate version for pilots (who had armored seats, such as they were) and a two plate versions for gunners/crew chiefs. Coverage was 70% of chest and weight was 6.8kg for 1 plate version and 13.6 kg for 2 plate version. They were supposedly proof against .30 caliber (Level 3 rifle?).

Police Vests:
Most police use concealable vests ranging in NIJ Level from 2A to 3A during the 90's. The Level 2A/2 vest would have been the most common vests for police. Level 3A concealable vests were rare but did exist (there are the remnants of an RBR Level 3a bought in 1997 sitting on my workbench right now...the victim of ballistic testing by your's truly). By the 90's, Level 1 material was limited to making "Ballistic Clothing" such as umbrellas and suit coats.
There were generally THREE coverage levels for concealable vests which are still available today;

Full Coverage Vest: This vest covers 80% of the chest and 60% of the abdomen for "Over-Vests" (worn outside of a shirt) and 80% of the chest and 40% of the abdomen for concealable vests (worn under a shirt).

Contour Coverage Vest: This vest is generally a concealable type that allows more flexibility/agility than full coverage vests without reducing protection too much. Contour vests cover 70% of the chest and 20% (or less) of the abdomen.

MiniWrap Coverage: This vest is always a concealable type and is usually worn by those concerned with hiding the fact that they are wearing armor. As a result, MiniWrap covers just 50% of the wear's chest. There is no abdominal coverage.

Trauma Plate Pockets: These special pockets are sewn on the outside of soft body armor and allow the placement of an additional soft panel or hard trauma plate to protect the chest (in the heart area). Some body armors may also have a trauma plate pocket over the spine as well. MiniWrap body armors generally don't have trauma plate pockets.
There are two sizes of trauma pocket, small and large.
Small pockets allow 20% coverage of the chest with the added panel/plate.
Large pockets allow 40% coverage of the chest with the added panel/plate.

[swaghauler]

Armor in Twilight2000 is compared to armor plate to determine Armor Value. Standard Armor Plate has a Brinell Hardness Rating of 500. It is stated in the Rules that 5mm of armor plate equals 1 Armor Value. Here is the Brinell Hardness Rating of other materials that you may need to determine the Armor Rating of;

Soft Wood (Pine): BH 1.6
Hard Wood (Oak to Mahogany): BH 2.6 to BH 7
Lead (Pure): BH 5
Lead (Alloyed): BH 22
Aluminum (Pure): BH 15
Aluminum (AW6060): BH 75
Mild Steel: BH 120
Stainless Steel Annealed (18-8/304): BH 200
AR500 Plate Steel/Armored Plate: BH 500
Hardened Tool Steel (Treated, Annealed): BH 600 to BH 900
Titanium: BH 700 to BH 2900
Titanium (6a1-7nb used in Aircraft/Bike Frames): BH 1600
Titanium (Enhanced/Armored): BH 2900
Synthetic Diamond: BH 4600

I hope these help you decide what protection a given material should provide.

[swaghauler]

As many of you already know, Speed Defeats Armor. Below is a sample chart to determine a weapon's Penetration based on the Velocity of the round it fires. This is a more realistic measure than Energy (like what is used in FFS) but I need to see some more "in game testing" (I use a slightly different system). I would appreciate any input from the forum on how this table affects the weapons in a more conventional game.

Velocity (ft/sec):
4001+ ft/sec ..................... Pen 1/2
3001 ft/sec to 4000 ft/sec .... Pen 1
2001 ft/sec to 3000 ft/sec .... Pen 2
1001 ft/sec to 2000 ft/sec .... Pen 3
1000 ft/sec or less .............. Pen 4

I use both the Shooter's Bible and Gun Digest to determine the velocity of various rounds but they are available online. I actually adjust the Penetration above by determining the velocity for each Range Band and then note the Penetration for that Range Band based on the Velocity. I also do this for Damage (I currently use the FFS damage calculator) too. I give Handguns a Penetration as well (no NIL here).

I would appreciate any input from the Forum.

swag.

[swaghauler]

I have calculated the Armor Values for both SAPI plates and ESAPI plates based on the NIJ Standards. These Standards are also fairly compatible with the Russian GOST-R, German ShutzKlasse 2008, and the British HOSDB Standards.

NIJ Level 3 (rifle)/SAPI Plate: 2 AV
NIJ Level 4 (rifle)/ESAPI Plate: 4 AV

You can also add the concealable vests worn by Law Enforcement too.

NIJ Level 2 Soft Body Armor: 1/2 AV
NIJ Level 1 Soft Body Armor: 1/4 AV

[Milano]

If I may add my 2 cents what is the difference between a 17 HMR traveling at 1300 f/s and a 338 Lapua Mag at 1300 f/s? Sectional Density. Instead of a straight look at the velocity I made up a formula that works fairly well. It is:

(1000/{speed in M/S}) x (Sectional Density) x (1.5325)

For example:

17 HMR 20 gr @ 1300 f/s -- DAM 1 PEN 3

.338 Lapua Mag 250 gr @ 1300 f/s -- DAM 4 PEN 3

(As an apples to apples comparison: the 17 is at 250 yards to drop to 1,300 f/s. The Lapua is at 1,285 yards to slow down to 1,300 f/s!!

Anyway I made an excel spreadsheet that makes all this fairly easy to figure out. Any question about how it works please ask. Here is the download:

[swaghauler]

If I may add my 2 cents what is the difference between a 17 HMR traveling at 1300 f/s and a 338 Lapua Mag at 1300 f/s? Sectional Density. Instead of a straight look at the velocity I made up a formula that works fairly well. It is:

(1000/{speed in M/S}) x (Sectional Density) x (1.5325)

For example:

17 HMR 20 gr @ 1300 f/s -- DAM 1 PEN 3

.338 Lapua Mag 250 gr @ 1300 f/s -- DAM 4 PEN 3

(As an apples to apples comparison: the 17 is at 250 yards to drop to 1,300 f/s. The Lapua is at 1,285 yards to slow down to 1,300 f/s!!

Anyway I made an excel spreadsheet that makes all this fairly easy to figure out. Any question about how it works please ask. Here is the download:

Nice system. It is similar to how I do my own system (which is still in development). I do change the Weapon Damage a bit, though. While I FFS's damage system, I round up or down in order to "include" or "exclude" certain calibers from certain damage classes based on my on experience. I use 1D10 damage for my rifles and double my calculated Damage when determining pistol damage... BUT I USE 1D6 TO REPRESENT PISTOL DAMAGE. In my game, a 9mmP does 2d6 and carries a PEN of 3. An AK-74 carries 2d10 DAM and has a PEN of 1 (steel core) or 2 (lead core) at Short Range.
I find that this modification to pistol damage makes them (and SMGs) more viable in the game.

[swaghauler]

I have calculated the Armor Values for both SAPI plates and ESAPI plates based on the NIJ Standards. These Standards are also fairly compatible with the Russian GOST-R, German ShutzKlasse 2008, and the British HOSDB Standards.

NIJ Level 3 (rifle)/SAPI Plate: 2 AV
NIJ Level 4 (rifle)/ESAPI Plate: 4 AV

You can also add the concealable vests worn by Law Enforcement too.

NIJ Level 2 Soft Body Armor: 1/2 AV

After watching several of MikeB's Youtube videos where he shoots all manner of weapons at old "steel pots," I would have to conclude that the majority of "steel pots" were only around NIJ Threat Level 2 or even 2A in protection. I would suggest that the Armor Value of a steel pot be 1/2 AV while the normally 3A "K-pots" remain at 1AV.

[.45cultist]

Less...... NIJ II....... an anemic 9mm or .38.

These are fragmentation vests, not bullet resistant. IBAs have a higher rating.

Yes, newer helmets are IIIA, supposedly a few of the later PAGSTs for LE use until the newer designs won out.

[swaghauler]

Yes, newer helmets are IIIA, supposedly a few of the later PAGSTs for LE use until the newer designs won out.

I have seen several tests on Youtube of the PASGT helmets and they stop all of the threats that an NIJ Level 3A vest would. This is everything up to mid-velocity .44 Magnum or 12 gauge slugs. They might "ring your bell," but the PASGT would let you keep your brains inside your skull.

[swaghauler]

I needed to find a way to take into account the fact that Armor can fail during play. Initially, I just used the Wear Value system but this only gave 10 hits or less. I KNOW (from my own testing) that even soft body armor can take much more than this. The RBR Level 3A Spectra Vest I referenced in my earlier post withstood 26 rounds of .40 S&W 165gr Jacketed Flat Points before letting one through and it is nearly 20 YEARS old with 6 years of daily wear under its belt. I have also seen Demolition Ranch's test of green tip 5.56mm against AR500 armor plate. That plate took 27 hits before a 5.56mm round got through it.

The new system I came up with involves reducing the vest's protection very gradually. I give the vest a "Coverage Rating" based on its actual "Real World" coverage. If a vest covers 80% of your body then its coverage rating is 16 or less on a 1D20 roll. EACH HIT THAT PENETRATES THE ARMOR (resisted hits don't count) REDUCES THIS RATING BY ONE. Thus, a vest with a Coverage Rating of 16 that had 3 rounds penetrate, now only covers the wearer on a roll of 13 or less. When the Coverage Rating reaches 0, the vest is ruined.

For those who want vests to provide 100% coverage to a location (like they do in the basic game), just start with a Coverage Rating of 20 (on 1D20).

Ceramic Vests:

Most ESAPI ceramic plates are NOT "multi-strike" rated. This means that one hit can compromise a plate. There are several instances where single strike plates have stopped multiple rounds. To reconcile this during play, I simply subtract the number of DICE OF DAMAGE OF A GIVEN ROUND from the plate's Coverage Rating for every round that penetrates. This balances out the plate's superior AV without requiring the player to put on new body armor after every hit.

This should add a little life to your player's body armor during play. As always, use what you will and ignore the rest.

Swag.

[Milano]

Umm it has been pointed out to me that the range calculation on the Excel file that I donated earlier is broken. Here is an updated fixed version...

[CDAT]

I needed to find a way to take into account the fact that Armor can fail during play. Initially, I just used the Wear Value system but this only gave 10 hits or less. I KNOW (from my own testing) that even soft body armor can take much more than this. The RBR Level 3A Spectra Vest I referenced in my earlier post withstood 26 rounds of .40 S&W 165gr Jacketed Flat Points before letting one through and it is nearly 20 YEARS old with 6 years of daily wear under its belt. I have also seen Demolition Ranch's test of green tip 5.56mm against AR500 armor plate. That plate took 27 hits before a 5.56mm round got through it.

The new system I came up with involves reducing the vest's protection very gradually. I give the vest a "Coverage Rating" based on its actual "Real World" coverage. If a vest covers 80% of your body then its coverage rating is 16 or less on a 1D20 roll. EACH HIT THAT PENETRATES THE ARMOR (resisted hits don't count) REDUCES THIS RATING BY ONE. Thus, a vest with a Coverage Rating of 16 that had 3 rounds penetrate, now only covers the wearer on a roll of 13 or less. When the Coverage Rating reaches 0, the vest is ruined.

For those who want vests to provide 100% coverage to a location (like they do in the basic game), just start with a Coverage Rating of 20 (on 1D20).

Ceramic Vests:

Most ESAPI ceramic plates are NOT "multi-strike" rated. This means that one hit can compromise a plate. There are several instances where single strike plates have stopped multiple rounds. To reconcile this during play, I simply subtract the number of DICE OF DAMAGE OF A GIVEN ROUND from the plate's Coverage Rating for every round that penetrates. This balances out the plate's superior AV without requiring the player to put on new body armor after every hit.

This should add a little life to your player's body armor during play. As always, use what you will and ignore the rest.

Swag.

Several years ago I went to a body armor shoot, the industry professional told us that to be rated as a level three plate it had to be able to take six shots (not in the same place), but that a level four plate was only rated for a single shot. He went on how just because that is what is required for the rating that does not mean that is the max it would take. They did not have any level four plates there and we wanted to try out our custom tungsten AP .30-06 rounds, so we sent a couple of rounds back with the rep, and they shot the plate (it stopped it) and sent the plate to us, we shot it tell we got one to penetrate (to about six rounds all in the same place). This was all mostly in regards to the ceramic plates, the steel plates were rated the same, but we better able to take the multi-strikes, but were much heavier. We also talk briefly about the polyethlene plates, that at the time could only be made into level III, but doing some looking today they can now be made in level four.

[swaghauler]

Several years ago I went to a body armor shoot, the industry professional told us that to be rated as a level three plate it had to be able to take six shots (not in the same place), but that a level four plate was only rated for a single shot. He went on how just because that is what is required for the rating that does not mean that is the max it would take. They did not have any level four plates there and we wanted to try out our custom tungsten AP .30-06 rounds, so we sent a couple of rounds back with the rep, and they shot the plate (it stopped it) and sent the plate to us, we shot it tell we got one to penetrate (to about six rounds all in the same place). This was all mostly in regards to the ceramic plates, the steel plates were rated the same, but we better able to take the multi-strikes, but were much heavier. We also talk briefly about the polyethlene plates, that at the time could only be made into level III, but doing some looking today they can now be made in level four.

It kind of reminds me of how the manufacturers won't warranty a soft vest older than 5 years because the fibers are supposed to wear out. My old RBR did very well despite nearly 6 years of daily wear and nearly 20 years of existence. I wouldn't have shot holes in it IF I HAD KNOWN IT WOULD STILL STOP ROUNDS LIKE THAT. I was impressed.

[The Dark]

I had been working on my own protection numbers prior to joining the board, since the 2.2 rules have minimal body armor. What I had come up with was that each NIJ type had AV equal to its type (i.e. Type I = AV1, Type IV = AV4). Types ending in A are half a point lower, with subtracted dice rounded down (so Type IIA is AV1.5; against Pen 1 it subtracts 1 die, against Pen 2 it subtracted 3 dice, etc).

Based on some of the tests mentioned by Dr. Bashford Dean in Helmets and Body Armor in Modern Warfare (Yale University Press, 1920), I'd put most trench armor at AV1 with a weight of 19 to 24 pounds. It won't stop rifle bullets up close, but it's moderately effective against pistols and long-range shots from many rifles. It was noted as resisting .30-06 service ammunition (2,780 fps muzzle velocity) at 300 yards, but failing at 60 yards. A low-powered rifle test at 2,140 fps penetrated at 30 yards but did not penetrate at 60 yards.

[swaghauler]

I had been working on my own protection numbers prior to joining the board, since the 2.2 rules have minimal body armor. What I had come up with was that each NIJ type had AV equal to its type (i.e. Type I = AV1, Type IV = AV4). Types ending in A are half a point lower, with subtracted dice rounded down (so Type IIA is AV1.5; against Pen 1 it subtracts 1 die, against Pen 2 it subtracted 3 dice, etc).

Based on some of the tests mentioned by Dr. Bashford Dean in Helmets and Body Armor in Modern Warfare (Yale University Press, 1920), I'd put most trench armor at AV1 with a weight of 19 to 24 pounds. It won't stop rifle bullets up close, but it's moderately effective against pistols and long-range shots from many rifles. It was noted as resisting .30-06 service ammunition (2,780 fps muzzle velocity) at 300 yards, but failing at 60 yards. A low-powered rifle test at 2,140 fps penetrated at 30 yards but did not penetrate at 60 yards.

How do you reconcile a level 2 kevlar vest stopping a 5.56mmN or a 7.62mmN rifle round when Penetration is calculated in? Do you change their penetration numbers or damage in any way, or do you just run a "Hollywood" type campaign? And don't get me wrong, I have NOTHING against "Hollywood, Space Opera, or High Fantasy" campaigns.... they can be the most fun. I just have a bunch of players who are shooters and combat veterans. They'll call "BS" on anything I introduce that's not based in reality (and this can occasionally be a real pain in the a**). I'd be interested in any changes you have made. I'm still trying to reconcile my AV ratings to stop pistols but not affect rifles as much.

[The Dark]

How do you reconcile a level 2 kevlar vest stopping a 5.56mmN or a 7.62mmN rifle round when Penetration is calculated in? Do you change their penetration numbers or damage in any way, or do you just run a "Hollywood" type campaign? And don't get me wrong, I have NOTHING against "Hollywood, Space Opera, or High Fantasy" campaigns.... they can be the most fun. I just have a bunch of players who are shooters and combat veterans. They'll call "BS" on anything I introduce that's not based in reality (and this can occasionally be a real pain in the a**). I'd be interested in any changes you have made. I'm still trying to reconcile my AV ratings to stop pistols but not affect rifles as much.I haven't changed it, although after looking a bit more, I may need to in order to keep high-powered rounds from being less useful. I'm mostly OK with how 5.56mmN interacts, since it only fails at long or extreme range (Dam 3, Pen 1-Nil, so at short or medium 1 die is still getting through). So an M-16 will penetrate up to 110 meters and an M4 at up to 68 meters. 7.62mmN's Dam 4, Pen 2-3-Nil is more problematic, since it won't penetrate at all. I'll need to look into some sort of mechanic for high-powered rounds. My first thought (and totally not playtested) is to give a 1 point penetration bonus for rounds that are either double the armor's value or the armor's value +2 (those are two different options), with a minimum of 1 and no change to Nils (so 1-Nil would remain 1-Nil, 2-3-Nil would become 1-2-Nil, etc). Either would allow 7.62mmN to be considered 1-2-Nil against 1 or 2 point armor, which would let it penetrate Class II up to medium range and Class I up to long range. The difference is that the blowthrough would be at either 3, 4, 5, and 6 or at 2, 4, 6, and 8 for the four classes of armor. My first inclination is to go with 3, 4, 5, 6 to keep most pistols out of the world of armor penetration.

[pmulcahy11b]

I have a PBI I've been rolling around my head for years, but haven't put in any real work on.

Basically, each vest (and ballistic plates, if applicable) type would stop a certain percentage of hits coming in. For every five points of damage stopped (rounding up), one point of blunt trauma is assessed. The old penetration figures stop five more points and assess one more point of PEN listed, and the PC is assessed one point for every five points the incoming round stops.

The problem is the old penetration figures. How to integrate them? I know I'm not doing it the right way, but haven't put in the thought to fix it.

Is this a worthwhile idea? Should I proceed with it further? Does anyone else have any ideas on how this might be fixed?

[CDAT]

I haven't changed it, although after looking a bit more, I may need to in order to keep high-powered rounds from being less useful. I'm mostly OK with how 5.56mmN interacts, since it only fails at long or extreme range (Dam 3, Pen 1-Nil, so at short or medium 1 die is still getting through). So an M-16 will penetrate up to 110 meters and an M4 at up to 68 meters. 7.62mmN's Dam 4, Pen 2-3-Nil is more problematic, since it won't penetrate at all. I'll need to look into some sort of mechanic for high-powered rounds. My first thought (and totally not playtested) is to give a 1 point penetration bonus for rounds that are either double the armor's value or the armor's value +2 (those are two different options), with a minimum of 1 and no change to Nils (so 1-Nil would remain 1-Nil, 2-3-Nil would become 1-2-Nil, etc). Either would allow 7.62mmN to be considered 1-2-Nil against 1 or 2 point armor, which would let it penetrate Class II up to medium range and Class I up to long range. The difference is that the blowthrough would be at either 3, 4, 5, and 6 or at 2, 4, 6, and 8 for the four classes of armor. My first inclination is to go with 3, 4, 5, 6 to keep most pistols out of the world of armor penetration.

So I am a little confused, are you talking the NIJ ratings or the in game ratings? I think that you are talking the NIJ ratings but even the best soft armor (NIJ 3A) will not stop any rifle round. Or at least out to 100 meters (that is as far as our range at work can shoot), at that distance our M4's go through both sides and the target dummy and into the back stop. Having gone to several body armor shoots from the industries professionals (AKA sales reps) where we got to shoot vests with all kinds of things, not a single vest stopped rifle rounds tell we got to the hard plates.

So I guess I am asking are you trying to get more realistic? If so all rifles (not pistol caliber carbines) will penetrate them at just about any range that you can hit with, and even the rifle rated plates are only good for a limited number of hits (level III rated at six, level IV rated at one, but both last longer). Or are you trying to make it less lethal on the players?

[swaghauler]

I haven't changed it, although after looking a bit more, I may need to in order to keep high-powered rounds from being less useful. I'm mostly OK with how 5.56mmN interacts, since it only fails at long or extreme range (Dam 3, Pen 1-Nil, so at short or medium 1 die is still getting through). So an M-16 will penetrate up to 110 meters and an M4 at up to 68 meters. 7.62mmN's Dam 4, Pen 2-3-Nil is more problematic, since it won't penetrate at all. I'll need to look into some sort of mechanic for high-powered rounds. My first thought (and totally not playtested) is to give a 1 point penetration bonus for rounds that are either double the armor's value or the armor's value +2 (those are two different options), with a minimum of 1 and no change to Nils (so 1-Nil would remain 1-Nil, 2-3-Nil would become 1-2-Nil, etc). Either would allow 7.62mmN to be considered 1-2-Nil against 1 or 2 point armor, which would let it penetrate Class II up to medium range and Class I up to long range. The difference is that the blowthrough would be at either 3, 4, 5, and 6 or at 2, 4, 6, and 8 for the four classes of armor. My first inclination is to go with 3, 4, 5, 6 to keep most pistols out of the world of armor penetration.

I think you might find the use of a round's Sectional Density rating of value here. Milano has really put in work on integrating "real world ballistics" into the game. SD is determined by the formula:

Sectional Density = bullet weight (in grains)/ [7000 X bullet diameter (in inches) X bullet diameter (in inches)].

Sectional densities range from less than 1 to more than 3 and give shooters a way to rate a bullet's performance on the four sizes of "game animal." Animals (including humans) are broken into four categories known as CPX ratings. These CPX Ratings are:

CPX-1, Varmints: These are animals up to about 50lbs. The Sectional Density used should be above 1 and up to 2.
CPX-2, Medium Game: These include larger sized game that is "thin skinned" up to about 250lbs. Humans are CPX-2 and a Sectional Density around 2.5 is considered a very good "stopper" for a man.
CPX-3, Large Game: These include still larger sized game such as bear, moose, or certain African big game. These animals REQUIRE a bullet with a Sectional Density above 3 for it to be effective in stopping CPX-3 game.
CPX-4?, Dangerous Game: This list includes the largest of the dangerous game. Rhino, Elephants, and Hippo's all fall into this category and a bullet should have a Sectional Density of around 3.5 to ensure a lethal hit on these animals.

You could use the sectional density of the round to modify that caliber's Penetration value. I would use the following modifiers based on Sectional Density:

SD of less than 1 = Increase PEN by 1 level (3 becomes 4).
SD of 1 to 1.9 = No increase in PEN.
SD of 2 to 3 = Decrease of 1 in PEN (3 becomes 2).
SD of more than 3 = Decrease of 2 in PEN (3 becomes 1).

I also use a round's Velocity to determine Penetration. I have modified my original chart to take into account real world ballistics AND to better "mesh" with Twilight's integrated Penetration-Damage-Armor Value system.

My Penetration Ratings have changed to the following:

5400fps or more = 1/4 PEN
4000fps to 5400fps = 1/2 PEN
2800fps to 4000fps = 1 PEN
1800fps to 2800fps = 2 PEN
1000fps to 1800fps = 3 PEN
1000fps or less = 4 PEN

I "overlap" my velocity numbers to give the developer/GM the flexibility to round up or down based on a round's real world performance characteristics.

I also allow for modification of PEN for certain designs of ammo. If a round is known for good penetration BUT has a lower Sectional Density (like the various PDW rounds such as .30 Carbine or the 5.7mm X 28mm), you can "swap" Damage for Penetration. The best formula I have found is to Multiply a round's Velocity by X1.5 to find its PEN Number. Nothing is free, though. If this modification to PEN is made, the round's Damage must be recalculated as well. Multiply the Energy of that round by X0.75 to find the new (reduced) DAM of that round at a given range. This is the "tradeoff" for increased PEN. For example:

The 7.62 Tokarev round is well known for its penetration, being able to punch through EVERY cold war helmet and easily penetrating NIJ Level 2A soft armor in its military steel-cored loading. The 90grn steel cored military round averages 1460fps and achieves 426ft/lbs of muzzle energy. Using the formulas above, the 7.62's PEN improves to 2 (from 3) when you multiply 1460fps by X1.5 (2190fps). Its Damage drops from 3d6 (for an energy from 401ft/lbs to 600ft/lbs) to 2D6 (for an energy from 250ft/lbs to 400ft/lbs) when its Energy of 426ft/lbs is multiplied by X0.75 for 319ft/lbs of energy. This gives it the ability to penetrate NIJ Level 2/2A armor (1/2 AV) while still being stopped by NIJ Level 3A armor (AV1) just like it is in real life.

These newer numbers are based on about 3 months of in-game play and seem to be working ok now.

I highly recommend several Youtubers for those interested in Armor Testing and Materials Penetration testing. Check out:

The Military Arms Channel: Tim was the first person to test Dyneema NIJ Level 3 (rifle) armor and has several interesting videos.

The Wound Channel: He was one of the first YouTubers to discover that 3000fps is the threshold for penetrating an NIJ Level 3 (rifle) plate. He also demonstrates that M193 Ball actually penetrates BETTER than the SS109/M855 round. I HIGHLY RECOMMEND HIM.

The Chopping Block: Much like the Wound Channel, He does a lot of armor/penetration testing.

MikeB: He has shot virtually EVERY helmet made in the 20th Century. Go here to see the 7.62T punch through EVERYTHING but the PASGT helmet.

ShootingTheBull.410: This man has test HUNDREDS of rounds in ballistic gel. He is a true authority on "stopping power" as the FBI tests for it.

These are just a few of the better YouTubers out there. There are others such as PocketGunsandGear, TN9Outdoors, ScubaOz, Taofledermouse, and DemolitionRanch. I hope you can use some of this to fix your issues.

Swag.

[swaghauler]

I have a PBI I've been rolling around my head for years, but haven't put in any real work on.

Basically, each vest (and ballistic plates, if applicable) type would stop a certain percentage of hits coming in. For every five points of damage stopped (rounding up), one point of blunt trauma is assessed. The old penetration figures stop five more points and assess one more point of PEN listed, and the PC is assessed one point for every five points the incoming round stops.

The problem is the old penetration figures. How to integrate them? I know I'm not doing it the right way, but haven't put in the thought to fix it.

Is this a worthwhile idea? Should I proceed with it further? Does anyone else have any ideas on how this might be fixed?

The relationship between Armor Values, Damage, and Penetration is ALWAYS the problem. Fix one...break another. It can get frustrating pretty fast.

It may sound funny, but I actually began using a system similar to what you propose for less-than-lethal damage in Twilight2000. I CANNOT EVEN REMOTELY CLAIM CREDIT FOR IT THOUGH. I "lifted" the Stun Damage system from Fantasy Hero for use in my game. I give each player a number of DAMAGE DICE (not points) equal to their HTH Damage Rating. This damage (using #D6 for punches, & #D10 for kicks) is all stun damage. Every 5 FULL POINTS OF STUN DAMAGE EQUAL 1 POINT OF WOUND DAMAGE to the location hit (figured from the damage rolled). Each location also has a "Stun Multiplier" (X1/2 for limbs, X1 for chest, X1.5 for abdomen, & X2 for head) to multiply the stun damage (only) and a player has five damage levels just like the Wound Thresholds.... Light, Medium, Serious, Critical and Deadly wound levels.
Those thresholds act like fatigue and a wound that exceeds your Deadly Stun Threshold renders you unconscious. I figure each Stun Damage Wound threshold by adding STR & CON. Thus a person with a STR of 5 and a CON of 5 would have a 10 Light Stun Level and a 50 Deadly Stun wound threshold.

I'll have to think about how you may improve your "Armor Ablation System(?)" for play. I'm not really sure what would work best right now.

[The Dark]

So I am a little confused, are you talking the NIJ ratings or the in game ratings? I think that you are talking the NIJ ratings but even the best soft armor (NIJ 3A) will not stop any rifle round. Or at least out to 100 meters (that is as far as our range at work can shoot), at that distance our M4's go through both sides and the target dummy and into the back stop. Having gone to several body armor shoots from the industries professionals (AKA sales reps) where we got to shoot vests with all kinds of things, not a single vest stopped rifle rounds tell we got to the hard plates.

So I guess I am asking are you trying to get more realistic? If so all rifles (not pistol caliber carbines) will penetrate them at just about any range that you can hit with, and even the rifle rated plates are only good for a limited number of hits (level III rated at six, level IV rated at one, but both last longer). Or are you trying to make it less lethal on the players?The problem is dealing with weapons at the high end of the pistol range and low end of the rifle range.

Using book values, the two .44 Magnum revolvers are both Dam 3, Pen 2-Nil. The M16A1 is Dam 2, Pen 1-Nil. AV 1 will be penetrated by both, AV 2 will be resisted by both.

Using Paul's damage values, the .44 Magnum is Dam 4, Pen 1-Nil, and the M16A1 is Dam 3, Pen 1-Nil, so it's impossible to protect against the .44 without also protecting against the M16 (the M4 is also 3, 1-Nil). You need AV 3 to protect against an M16 or M4, and AV 4 to protect against the .44 Magnum. Since NIJ Class IIIA is supposed to protect against .44 Magnum.


Going back to book values (and using the NIJ 0101.06 standard), each level needs to protect against the following:
IIA: 9mm, .40 S&W: no .40 S&W weapon is in IWW, and all the 9mm pistols are Pen Nil.
II: 9mm, .357 Magnum: .357 Magnum is Dam 2, Pen 1-Nil.
IIIA: .357 SIG, .44 Magnum: Only 9mm Sigs are included, but .44 Magnum is Dam 3, Pen 2-Nil.
III: 7.62x51mm: Every rifle in IWW using 7.62mmN is Dam 4, Pen 2-3-Nil.

Looking at it this way, it becomes clear that the damage and pen values are the problem. AV2 is the minimum to protect against .357 Magnum, but it also protects against 7.62x51mm and .44 Magnum.

If we use numbers from the weapons Paul has done up:
IIA: the .40S&W Glock 22/23 series are Dam 2, Pen 1-Nil
II: the S&W Model 13 (.357 Magnum) is Dam 3, Pen 1-Nil
IIIA: the S&W Model 29 (.44 Magnum) is Dam 4, Pen 1-Nil
III: the Springfield M14 is Dam 4, Pen 2-3-Nil

Paul's numbers would work if we change the Pen around. It doesn't really make sense that pistol rounds (slower and heavier) have better Pen, since velocity is what matters (as swag mentioned). If all the pistols mentioned become 2-Nil, and the M14 is 1-2-Nil, then we end up in a situation where AVs of 1 (for IIA), 1.5 (for II), 2 (for IIIA), and 4 (for III with plates) will work against the appropriate weapons. An M-16, with Dam 3 and Pen 1-Nil, will penetrate up to IIIA and be stopped by III. This is better, but it's not systematic yet.

The problem extends into Fire, Fusion & Steel, where low-powered rounds (between 600 and 2000 joules muzzle energy) are the best penetrators. Get a round up to 1990 joules (but don't go over 2000), and you'll get Dam 3, Pen 1-Nil; the next time something will be able to penetrate AV2 is at 6807 joules, when you get Dam 5 and Pen 2-3-4. The solution would be to rewrite the Penetration table so that each step is no worse than the step before. As it stands, there are two "bad" steps - going from 1-Nil to 2-Nil at 2000 joules, and from 2-3-Nil to 2-4-6 at 5000 joules. I don't have that solution yet (i.e. a rewritten Pen table for FF&S), but at least now the problem seems clear.

[The Dark]

Following up from my last post, the biggest issue with having multiple types of armor is that the interaction of Dam and Pen stats gives no real range of plausible AVs, since the same AV2 armor is the minimum to protect against both a .357 Magnum and a 7.62x51mm shot. As such, here's my suggested change in Pen values for firearms:

If Pen WAS Nil, it now IS Nil
If Pen WAS 1-Nil, it now IS 2-Nil
If Pen WAS 2-Nil, it now IS 2-4-Nil
If Pen WAS 2-3-Nil, it now IS 2-4-6
If Pen WAS 2-4-6, it now IS 2-3-4
If Pen WAS 2-3-4, it now IS 2-2-3
If Pen WAS 2-2-3, it now IS 1-2-3

Damage dice may need to be adjusted slightly; I would change the M14 to Dam 5 so that it penetrates AV2 at close/medium and AV1 at long range with its new Pen 2-4-6. Meanwhile, the .357 Magnum can be stopped by AV1.5 and the .44 Magnum by AV2. Suggested AVs would be:
NIJ IIA: 1 (defeats the Dam 2, Pen 2-Nil pistol rounds)
NIJ II: 1.5 (defeats the Dam 3, Pen 2-Nil .357 Magnum)
NIJ IIIA: 2 (defeats the Dam 4, Pen 2-Nil .44 Magnum)
NIJ III: 2.5 (defeats the Dam 5, Pen 2-4-6 7.62x51mm)

Also, blunt trauma is suffered at a rate of 1 point per AV of damage prevented (minimum 1), rather than 1 for 1, so someone shot with a Dam 2, Pen 2-Nil pistol while wearing IIIA armor (AV2) takes 1 point of trauma damage, rather than 2.

Rounds known for armor penetration would subtract 1 from their Pen (so 2-Nil would become 1-Nil, 1-2-3 would become 1-1-2) and also subtract 1 from all damage dice. The P-90 (Dam 2, Pen 1-Nil on Paul's page) would be Dam 2, Pen 2-Nil under this system, but based on the 5.7mm being designed for penetration, it's modified to Dam 2-2, Pen 1-Nil.

This will still need some ironing out, I'm sure. The M16 is a clear problem, since it becomes Dam 3, Pen 2-Nil under this system, which is far too weak. Considering it AP lets it defeat NIJ III armor, which I'm not happy about, but the other solution is likely to up it to Dam 5, since it should be able to defeat NIJ IIIA. Maybe the trauma plates should add a full AV and NIJ III should be AV 3?

[swaghauler]

The Dark:

NIJ Level 3 (Rifle): I wouldn't worry about 5.56mmN penetrating NIJ Level 3 (rifle) plates. Level 3 rifle plates (which are representative of SAPI plates too) are only rated for 7.62mm NATO rounds of 147grn weight at a velocity of 2780 fps. The 5.56mm NATO round has a velocity ranging from 2800 fps (M855) to 3100 fps (M193) and has ROUTINELY penetrated SAPI plates at short range. This is why my PEN numbers for an M16A2 (DAM 2D10/2D10/2D10/1D10) are 1/2/2/3. It can penetrate a SAPI plate in its older lead configuration (newer copper bullets seem to have trouble here).

NIJ Level 4/ESAPI standard plates: I haven't seen you post anything about NIJ Level 4/ESAPI plates so I thought I might mention them here. They are rated to stop at least a single 166grn 3006 Armor Piercing round at 2780 (today this round would be considered only an "enhanced penetrator" compared to the Tungsten and DU rounds in service now). It stops ALL 5.56mmN rounds as well as all 7.62mmN rounds.

NIJ Level #+ plates/inserts: Any vest you see that features a + after its rating is a vest NOT rated by the NIJ. The manufacturer of these vests Guarantees that it meets the level standard (ie Level2+, Level3+...the most common types) that precedes the + but is claiming that vest actually EXCEEDS that standard. The problem with this is it may JUST EXCEED the rating or it may be at virtually the next NIJ Level of protection. Since tests vary from manufacturer to manufacturer, you are basically "blind" as to the vest's true rating.

Pistols, Rifles, Soft, and Hard Armors:

If you keep having balance issues, you can try differentiating between Pistol Rounds and Rifle Rounds as well as between Soft Body armors (designed for pistols) and Hard Body armors. I would try designating DAM with a "P" for pistol or an "R" for rifle. You then give your armor a suffix of "S" for soft vests and "H" for hard plate armors. Anytime RIFLE DAMAGE encounters SOFT ARMOR, just divide the armor rating in half (rounding down) BEFORE accounting for PEN to reflect the superior penetration of rifles. This, of course, would NOT APPLY to Hard armors.

Finally, I would have any "Surplus Protection" of HARD PLATE ARMORS reduce the BLUNT TRAUMA DAMAGE by that amount. This reflects instances where soldiers wearing SAPI/ESAPI plates have been hit but are completely uninjured (especially by long range fire). Knockdown Dice would still apply (I apply Knockdown if you are hit by a round with MORE DAMAGE DICE than the average of your STR and AGL).

[The Dark]

The Dark:

NIJ Level 3 (Rifle): I wouldn't worry about 5.56mmN penetrating NIJ Level 3 (rifle) plates. Level 3 rifle plates (which are representative of SAPI plates too) are only rated for 7.62mm NATO rounds of 147grn weight at a velocity of 2780 fps. The 5.56mm NATO round has a velocity ranging from 2800 fps (M855) to 3100 fps (M193) and has ROUTINELY penetrated SAPI plates at short range. This is why my PEN numbers for an M16A2 (DAM 2D10/2D10/2D10/1D10) are 1/2/2/3. It can penetrate a SAPI plate in its older lead configuration (newer copper bullets seem to have trouble here).I couldn't remember how 5.56mmN did against NIJ III, but based on your post and a comment on an armor manufacturer's site, I think the M193 round should definitely be Dam 3-3 Pen 1-Nil. I'm still not sure about the SS-109, which isn't quite as good a penetrator. It's better than a pure lead core, but it's not up to the same level as the M193 - SAPI plus an Interceptor vest has to survive three Green Tip strikes in order to meet the standard (along with three 7.62x39mm and three 7.62x54mmR).

NIJ Level 4/ESAPI standard plates: I haven't seen you post anything about NIJ Level 4/ESAPI plates so I thought I might mention them here. They are rated to stop a single 166grn 3006 Armor Piercing round at 2780 (today this round would be considered only an "enhanced penetrator" compared to the Tungsten and DU rounds in service now). It stops ALL 5.56mmN rounds as well as all 7.62mmN rounds.I hadn't gotten to that one yet, since I wanted to make sure I had the II and III balanced before moving on to the IV. Since an armor-piercing .30-06 round should be Dam 4-4, AP 1-2-Nil, AV4 would suffice. As a side note, NIJ IV is rated to stop at least one round. The manufacturer can tell the lab to fire up to six shots at each panel, which is why their required number of armors for testing is wildly variable, from 7 to 37, since the test requires 36 shots, which could be on 6 armors or 36 armors, depending on the manufacturer's specifications (1 armor is a spare). However, without knowing a specific manufacturer's direction to the test lab, NIJ IV has no requirement above that one shot. ESAPI requires three shots from 5.56mmN, 7.62x39mm, 7.62x54mm, and .30-06AP, though for the last round only the first two shots are counted for pass/fail.

NIJ Level #+ plates/inserts: Any vest you see that features a + after its rating is a vest NOT rated by the NIJ. The manufacturer of these vests Guarantees that it meets the level standard (ie Level2+, Level3+...the most common types) that precedes the + but is claiming that vest actually EXCEEDS that standard. The problem with this is it may JUST EXCEED the rating or it may be at virtually the next NIJ Level of protection. Since tests vary from manufacturer to manufacturer, you are basically "blind" as to the vest's true rating.A + is supposed to indicate that an armor has been tested to that level, and against an additional type of bullet as well, although I'm not sure how well that's enforced (and since only five labs are NIJ-certified, they'd be very busy with all the armor types being promoted these days). The NIJ test has allowances for non-standard armor (in the 0101.06 procedure, it's section 2.6 and Appendix B). Appendix B also has rounds that are "special threat rounds" that are considered "of particular concern to law enforcement," which could probably be considered AP rounds for the purpose of these rules.

Pistols, Rifles, Soft, and Hard Armors:

If you keep having balance issues, you can try differentiating between Pistol Rounds and Rifle Rounds as well as between Soft Body armors (designed for pistols) and Hard Body armors. I would try designating DAM with a "P" for pistol or an "R" for rifle. You then give your armor a suffix of "S" for soft vests and "H" for hard plate armors. Anytime RIFLE DAMAGE encounters SOFT ARMOR, just divide the armor rating in half (rounding down) BEFORE accounting for PEN to reflect the superior penetration of rifles. This, of course, would NOT APPLY to Hard armors.I think the adjusted Pen stats, plus shifting armor to be 1 (for IIA) to 4 (for IV) solves the problem for most rounds. I do still need to look at some of the newer rounds (like 6.5mm Grendel or 6.8mm Remington SPC) to determine if they're more like the >7mm "brute force" rounds or the <6mm AP rounds. Since pistols are pretty much all 2-Nil, and the exceptions are relatively weak (the Five-seveN, for example), the only real trick is balancing out the rifles.

Finally, I would have any "Surplus Protection" of HARD PLATE ARMORS reduce the BLUNT TRAUMA DAMAGE by that amount. This reflects instances where soldiers wearing SAPI/ESAPI plates have been hit but are completely uninjured (especially by long range fire). Knockdown Dice would still apply (I apply Knockdown if you are hit by a round with MORE DAMAGE DICE than the average of your STR and AGL).Yes, I agree that the plates should reduce blunt trauma damage. I even think the heavy soft armors should have some reduction:

SOFT armor: Divide number of dice of damage stopped by AV and round up; this is the blunt trauma damage taken.
HARD armor: Divide number of dice of damage stopped by AV and round down. Subtract any excess AV. This is the blunt trauma damage taken.

Examples using a close-range .44 Magnum (Dam 4, Pen 2-Nil):
Against IIA, 2 points of damage are absorbed. Target takes 2d6 and 2 blunt trauma
Against IIIA, all damage is absorbed. The 4 dice are divided by 2 (the AV), and the target takes 2 blunt trauma
Against III, all damage is absorbed. The 4 dice are divided by 2.5, giving 1.6, rounded DOWN to 1. The armor can absorb 5 dice, so an extra point is subtracted, and the target takes no damage.

Other things to keep in mind with this system - armor only protects where it covers; for most modern armors, that's the chest and abdomen, with maybe a 50% arm coverage. That still leaves a target with 40% uncovered on the legs, either 10 or 20% uncovered on the arms, and (probably) 3.3% uncovered on the head. At best, armor will protect against slightly less than half of random hits. Also, Outstanding Success will allow penetration of armors that would normally protect (an Outstanding Success by the .44 Magnum against NIJ III would cause 3d6 damage and 2 blunt trauma).

[CDAT]

The Dark:

NIJ Level 3 (Rifle): I wouldn't worry about 5.56mmN penetrating NIJ Level 3 (rifle) plates. Level 3 rifle plates (which are representative of SAPI plates too) are only rated for 7.62mm NATO rounds of 147grn weight at a velocity of 2780 fps. The 5.56mm NATO round has a velocity ranging from 2800 fps (M855) to 3100 fps (M193) and has ROUTINELY penetrated SAPI plates at short range. This is why my PEN numbers for an M16A2 (DAM 2D10/2D10/2D10/1D10) are 1/2/2/3. It can penetrate a SAPI plate in its older lead configuration (newer copper bullets seem to have trouble here).

I am not sure where you are getting your information, but having shot level 3 plates with lots of different 5.56mm rounds if it is a level 3 plate it has to be rated to stop six separate rounds. So if a SAPI will not it is not a level 3 plate. The LE level 3 plates we shot would stop green (semi-AP) and even black tip (true AP) 5.56mm. At the shoots we did not get any vest to fail tell we were into the double digests of rounds. The manufactures provided the vests, we (the LE departments) the guns and ammo.

NIJ Level 4/ESAPI standard plates: I haven't seen you post anything about NIJ Level 4/ESAPI plates so I thought I might mention them here. They are rated to stop a single 166grn 3006 Armor Piercing round at 2780 (today this round would be considered only an "enhanced penetrator" compared to the Tungsten and DU rounds in service now). It stops ALL 5.56mmN rounds as well as all 7.62mmN rounds.

As for the Level 4, the agency I was with had .30-06 custom Tungsten perpetrators designed to stop armored cars, the level 4 vests we shot that are only rated to stop one round, failed just after ten rounds in close to the same area (none of us were good enough shots to hit the same area, but we were all with in the X ring close to each other).

[The Dark]

I am not sure where you are getting your information, but having shot level 3 plates with lots of different 5.56mm rounds if it is a level 3 plate it has to be rated to stop six separate rounds. So if a SAPI will not it is not a level 3 plate. The LE level 3 plates we shot would stop green (semi-AP) and even black tip (true AP) 5.56mm. At the shoots we did not get any vest to fail tell we were into the double digests of rounds. The manufactures provided the vests, we (the LE departments) the guns and ammo.There are some level 3s that the manufacturers state won't reliably stop the black tip. I think that, for gaming purposes, having the green tip be Dam 3 Pen 2-Nil and the black tip be Dam 3-3 Pen 1-Nil is a workable compromise. There are so many variations on 3 and 3+ that cover very specific rounds that a body armor system could easily become unplayably complex.


As for the Level 4, the agency I was with had .30-06 custom Tungsten perpetrators designed to stop armored cars, the level 4 vests we shot that are only rated to stop one round, failed just after ten rounds in close to the same area (none of us were good enough shots to hit the same area, but we were all with in the X ring close to each other).That's a novel use for perps. :D

I do appreciate the anecdotes, though. For someone like me who rarely even sees armor outside of a museum, it's useful to get information from someone who's not trying to sell the armor.

[CDAT]

There are some level 3s that the manufacturers state won't reliably stop the black tip. I think that, for gaming purposes, having the green tip be Dam 3 Pen 2-Nil and the black tip be Dam 3-3 Pen 1-Nil is a workable compromise. There are so many variations on 3 and 3+ that cover very specific rounds that a body armor system could easily become unplayably complex.

However you want to do it, just giving info from my experiences. And you get what you paid for it regardless of how/if you use it. Sometimes it is so easy to get bogged down with the details to miss out on the fun.

That's a novel use for perps. :D

I do appreciate the anecdotes, though. For someone like me who rarely even sees armor outside of a museum, it's useful to get information from someone who's not trying to sell the armor.

Going to the body armor shoot was a lot of fun, they let us shoot it with just about anything we wanted, they were even going to let us use the .30-06 on the level 3, until we broke out our ammo, one look at it and they would not let us use it on the level 3 plates, ball they were fine with, but did let us know that it was not rated for that round and may or many not stop it. We did not get to find out as we did not have any ball .30-06 with us.

[swaghauler]

I am not sure where you are getting your information, but having shot level 3 plates with lots of different 5.56mm rounds if it is a level 3 plate it has to be rated to stop six separate rounds. So if a SAPI will not it is not a level 3 plate. The LE level 3 plates we shot would stop green (semi-AP) and even black tip (true AP) 5.56mm. At the shoots we did not get any vest to fail tell we were into the double digests of rounds. The manufactures provided the vests, we (the LE departments) the guns and ammo.

I'm getting my info from the National Institute of Justice. The standards are that they test armor against 147grn 7.62mmN at @2780 fps ONLY. They do NOT test 5.56mmN in any of the NIJ Standards (I believe this is because LE wasn't using it when they wrote the initial testing standards in the 70's). The SAPI standard required stopping a 5.56mmN IN CONJUNCTION WITH an Interceptor soft plate (which is NIJ Level 3A) and NOT as a "stand alone" armor plate. this means you're backing an NIJ Level 3 plate with an NIJ Level 3A plate...in essence, giving that setup (in my game) an AV of 3. Most "stand alone" SAPI plates ROUTINELY perform at NIJ Level 3 (rifle) levels (which makes them no slouch in a "stand alone" configuration as well).
You may very well have had stops with 5.56mm, NO two manufacturer's armors are identical. Another factor may have been your rifles. If you were using actual M4's, their 14.5" barrels can reduce the velocity of the 5.56mmN by up to 300fps. The Level 3 plate does tend to stop any round NOT EXCEEDING 2750fps (and several rounds above 2800fps...cross-sectional density maybe?). Most testing in 5.56mmN is still done with a 20" barrel and the 3100fps velocity of M193 ball actually REQUIRES IT to hit 3100fps. Additionally, look at the new M855A1 ammo (with a 13% increase in velocity to more than 3100fps in a 62-grain projectile), It cuts right through an NIJ Level 3 vest at short range and STILL behaves like a Soft Point bullet inside the target. It could be as much of a "game changer" as MK282 was when it was introduced.
Check out both the Chopping Block and The Wound Channel on Youtube. They have the best videos of Level 3 plates being penetrated (usually by M193 ball due to its lighter grain weight/faster speed).

As for the Level 4, the agency I was with had .30-06 custom Tungsten perpetrators designed to stop armored cars, the level 4 vests we shot that are only rated to stop one round, failed just after ten rounds in close to the same area (none of us were good enough shots to hit the same area, but we were all with in the X ring close to each other).

I was wondering if you saw my mistake in the standards. I said one round when the standard is 3 rounds of AP. I'll make that correction today.
Once again, armor manufacturer's quality varies and there are several vests out there that EXCEED the minimum standard. I find it funny that the Standard is .30-06 AP, but that speaks to the age of the NIJ Standards as well (in addition to the state of "LE equipping" when they were written). Once again, 5.56mm (or 7.62mm) are NOT TESTED in this standard. The difference is that Level 4 plates ROUTINELY stop ALL 5.56mmN rounds...even though the velocity standard for this test is STILL only 2750fps (but with a hardened penetrator). ESAPI is, of course, a higher standard but any ESAPI plate is equal to, or better than NIJ Level 4.

[CDAT]

I'm getting my info from the National Institute of Justice. The standards are that they test armor against 147grn 7.62mmN at @2780 fps ONLY. They do NOT test 5.56mmN in any of the NIJ Standards (I believe this is because LE wasn't using it when they wrote the initial testing standards in the 70's). The SAPI standard required stopping a 5.56mmN IN CONJUNCTION WITH an Interceptor soft plate (which is NIJ Level 3A) and NOT as a "stand alone" armor plate. this means you're backing an NIJ Level 3 plate with an NIJ Level 3A plate...in essence, giving that setup (in my game) an AV of 3. Most "stand alone" SAPI plates ROUTINELY perform at NIJ Level 3 (rifle) levels (which makes them no slouch in a "stand alone" configuration as well).
You may very well have had stops with 5.56mm, NO two manufacturer's armors are identical. Another factor may have been your rifles. If you were using actual M4's, their 14.5" barrels can reduce the velocity of the 5.56mmN by up to 300fps. The Level 3 plate does tend to stop any round NOT EXCEEDING 2750fps (and several rounds above 2800fps...cross-sectional density maybe?). Most testing in 5.56mmN is still done with a 20" barrel and the 3100fps velocity of M193 ball actually REQUIRES IT to hit 3100fps. Additionally, look at the new M855A1 ammo (with a 13% increase in velocity to more than 3100fps in a 62-grain projectile), It cuts right through an NIJ Level 3 vest at short range and STILL behaves like a Soft Point bullet inside the target. It could be as much of a "game changer" as MK282 was when it was introduced.
Check out both the Chopping Block and The Wound Channel on Youtube. They have the best videos of Level 3 plates being penetrated (usually by M193 ball due to its lighter grain weight/faster speed).


I guess that I was not clear in what I was trying to say, I was more commenting on how you are the only one that I know of that talks about how a 5.56mm has better penetration than a 7.62mm. Also having looked a bit more into it SAPI plates are not rated by NIJ they are rated by ARMY MIL-STD-662F and STANAG 2920 Ed2, so have different standards (like where you pointed out that they are rated to stop with the vest, are not stand alone). As for the rifle used it was a semi-auto AR with 20 inch barrel, we used green tip, black tip, Mk 262 (I am guessing that is what you are talking about when you said Mk 282?) and a bunch of civilian rounds, we did not use the M855A1 I have heard great things about it, but no first hand experience. Some shots as close as 50ft, an never had a single round penetrate, however they were not SAPI plates, they were level III plates. I have not had the time to watch the videos, but going back over my notes from the training I did have a note how the Polyethylene Plates could have penetrations at some velocities, we did not shoot them we only shot the Ceramic and Steel Plates.

I was wondering if you saw my mistake in the standards. I said one round when the standard is 3 rounds of AP. I'll make that correction today.
Once again, armor manufacturer's quality varies and there are several vests out there that EXCEED the minimum standard. I find it funny that the Standard is .30-06 AP, but that speaks to the age of the NIJ Standards as well (in addition to the state of "LE equipping" when they were written). Once again, 5.56mm (or 7.62mm) are NOT TESTED in this standard. The difference is that Level 4 plates ROUTINELY stop ALL 5.56mmN rounds...even though the velocity standard for this test is STILL only 2750fps (but with a hardened penetrator). ESAPI is, of course, a higher standard but any ESAPI plate is equal to, or better than NIJ Level 4.
No, I did not see you mistake, as I was also told in my class it was one round for level four plates. This was just more a comment on how tough some of the vests are from actually shooting them not reading reports or watching videos but first hand doing. Kind of saying how just because something is rated for X that does not mean it can not do more, you may not want to count on it to do more but sometimes it can.

[The Dark]

Additionally, look at the new M855A1 ammo (with a 13% increase in velocity to more than 3100fps in a 62-grain projectile), It cuts right through an NIJ Level 3 vest at short range and STILL behaves like a Soft Point bullet inside the target. It could be as much of a "game changer" as MK282 was when it was introduced.There are still issues with the M855A1, although not related to penetration. When American Rifleman tested the round, about 20% were flyers (and that was a test this year, after the bismuth alloy that deteriorated in hot weather was supposedly fixed). The accuracy also isn't quite as good as advertised, because the tests were done with a tighter twist than service rifles have (either 1:8 or 1:9, instead of 1:7). The current standard for approval is 5.5 MOA.

Also, the ballistic trajectory isn't the same, so all the rifle sights (from iron to red dot) will need to be changed. It's fairly close up to 200 yards, but beyond that it rapidly diverges to a six inch change in elevation.

It also causes port erosion in M4 tests due to the much higher pressure, which affects automatic fire rate and increases jamming. A SOCOM test found that on average, a rifle firing M55A1 would crack a locking lug every 6,000 rounds. Even without a catastrophic failure of the rifle, barrel life is reduced by around 50% due to the high pressure of the round.

All of these problems can be overcome, through improved quality control and toughened internals. As for penetration, the information I've seen is that it will penetrate NIJ III armor, but will not penetrate SAPI. When the Wound Channel tested the round, it went through III easily. Against III+, it failed out of a 16" barrel but penetrated out of a 22" barrel (it also didn't generate nearly the advertised velocity, being 2960 fps out of the 16" (and 3259 out of the 22")). Unless TWC had some underpowered rounds, the M4 won't generate the advertised velocity (though the M16 should). This probably explains why the USMC (which intends to use the M4 only) is using the Mk318 SOST ammunition at 2925 fps from a 14" barrel instead of the M855A1.

[swaghauler]

I guess that I was not clear in what I was trying to say, I was more commenting on how you are the only one that I know of that talks about how a 5.56mm has better penetration than a 7.62mm. Also having looked a bit more into it SAPI plates are not rated by NIJ they are rated by ARMY MIL-STD-662F and STANAG 2920 Ed2, so have different standards (like where you pointed out that they are rated to stop with the vest, are not stand alone). As for the rifle used it was a semi-auto AR with 20 inch barrel, we used green tip, black tip, Mk 262 (I am guessing that is what you are talking about when you said Mk 282?) and a bunch of civilian rounds, we did not use the M855A1 I have heard great things about it, but no first hand experience. Some shots as close as 50ft, an never had a single round penetrate, however they were not SAPI plates, they were level III plates. I have not had the time to watch the videos, but going back over my notes from the training I did have a note how the Polyethylene Plates could have penetrations at some velocities, we did not shoot them we only shot the Ceramic and Steel Plates.

It has only recently been shown that plates can be penetrated by certain rounds and ALL of those rounds have a similar set of traits. Those traits are a Sectional Density of 0.15 to 2, a small diameter caliber (think about the 5.7 as well here) and a Velocity ABOVE 3000fps for Level 3/SAPI. Velocity it seems is the key to ARMOR PENETRATION (but not necessarily "barrier penetration"). Not just 5.56mmN but several rounds exceeding 3000fps have been found to penetrate armor plates. In soft armor, 1800fps seems to be the "threshold" to penetrate NIJ Level 3A soft armor (check out Tim at The Military Arms Channel's tests on Levels 2 and 3A soft armors) and 1400fps appears to be the "threshold" for penetrating NIJ Level 2 soft armor (check out the tests Tim does with 7.62mm X 25mm T military ball). This is why I'm "espousing" velocity as the primary measure for PEN (the stat) in Twilight2000. Keep in mind that while a 5.56mmN 55grain M193 will penetrate a Level 3 plate at close range (turning the BATF's AP argument against M855 completely on its head); But, once its velocity drops below 3000fps, it will NOT penetrate the plate (which can happen as close as 40 meters out). This is why I figure PEN (the stat) for EACH Range Band based on a round's velocity for that range band (I use the range at the middle of said range band for this). This not only adds variety to the game but also provides certain limitations on some weapons. For instance, just because the 20" barreled M16A2 can penetrate NIJ Level 3 at Short Range doesn't mean that the 14.5" barreled M4 can. It gives a player a choice to make, the lighter, handier, M4 or more effective (with regards to range and PEN) M16A2.
The 7.62mmN will NOT have the PEN (the stat) that 5.56mmN has but DON'T look at 7.62 through the narrow lens of just the PEN stat. In my game, it has 4D10 Damage dice (at Short range) to 5.56mmN's 2D10 Damage. You have to look at DAM and PEN as a unit to really determine what a given round can penetrate. This is why I use a round's Energy to determine the DAM it can do (as per FF&S/Small Arms Guide formulas). I do this by Range Band too. The 5.56mmN may look impressive because it MAY (depending on barrel length) penetrate a Level 3 plate at short range, but look further out in Range Bands and you will see WHY 7.62mm is still used in MGs and Sniper Rifles (5.56mm begins to lose its "shine" starting at Medium Range). My point here is DO NOT look at PEN ALONE, you must assess PEN & DAM TOGETHER for an accurate view of what a round can do.

Thanks for catching that Typo on MK 262. I was talking about the Black Hills 77grn Open-Tipped Match round. The only 5.56mm N round in my game to make the 3D10 threshold (I modified the DAM calculation slightly by rounding up or down in various steps). It won't penetrate a Level 3 plate either (its lowered velocity nets it a PEN of 2).

No, I did not see you mistake, as I was also told in my class it was one round for level four plates. This was just more a comment on how tough some of the vests are from actually shooting them not reading reports or watching videos but first hand doing. Kind of saying how just because something is rated for X that does not mean it can not do more, you may not want to count on it to do more but sometimes it can.

I couldn't agree more. I have sacrificed 2 helmets, 2 soft vests, and a hard trauma plate (NIJ Level 3) to "see for myself" just how effective armor is.

[swaghauler]

There are still issues with the M855A1, although not related to penetration. When American Rifleman tested the round, about 20% were flyers (and that was a test this year, after the bismuth alloy that deteriorated in hot weather was supposedly fixed). The accuracy also isn't quite as good as advertised, because the tests were done with a tighter twist than service rifles have (either 1:8 or 1:9, instead of 1:7). The current standard for approval is 5.5 MOA.

Also, the ballistic trajectory isn't the same, so all the rifle sights (from iron to red dot) will need to be changed. It's fairly close up to 200 yards, but beyond that it rapidly diverges to a six inch change in elevation.

It also causes port erosion in M4 tests due to the much higher pressure, which affects automatic fire rate and increases jamming. A SOCOM test found that on average, a rifle firing M55A1 would crack a locking lug every 6,000 rounds. Even without a catastrophic failure of the rifle, barrel life is reduced by around 50% due to the high pressure of the round.

All of these problems can be overcome, through improved quality control and toughened internals. As for penetration, the information I've seen is that it will penetrate NIJ III armor, but will not penetrate SAPI. When the Wound Channel tested the round, it went through III easily. Against III+, it failed out of a 16" barrel but penetrated out of a 22" barrel (it also didn't generate nearly the advertised velocity, being 2960 fps out of the 16" (and 3259 out of the 22")). Unless TWC had some underpowered rounds, the M4 won't generate the advertised velocity (though the M16 should). This probably explains why the USMC (which intends to use the M4 only) is using the Mk318 SOST ammunition at 2925 fps from a 14" barrel instead of the M855A1.

There is NO QUESTION that the round has not been fully developed. I just hope they don't kill a thousand soldiers by rushing it into the field.

[The Dark]

There is NO QUESTION that the round has not been fully developed. I just hope they don't kill a thousand soldiers by rushing it into the field.It's been in use since 2010 (the Army announced the first shipment to a field unit on 23 June 2010) and at least a couple hundred million rounds have been ordered (~150 million in FY13 and ~65 million in FY15; I haven't run across numbers for other FYs yet). For current use, I'm more in favor of the Mk318, which is around half the cost of the M855A1, is a 62 grain round, and fires at around 2900 FPS from an M4 and 3100 FPS from an M16, using a solid copper slug behind a copper/lead point for use as a barrier blind round. The bronze tip might end up being better in the long run, but that 13% chamber pressure increase gives me the heebie-jeebies.

[swaghauler]

It's been in use since 2010 (the Army announced the first shipment to a field unit on 23 June 2010) and at least a couple hundred million rounds have been ordered (~150 million in FY13 and ~65 million in FY15; I haven't run across numbers for other FYs yet). For current use, I'm more in favor of the Mk318, which is around half the cost of the M855A1, is a 62 grain round, and fires at around 2900 FPS from an M4 and 3100 FPS from an M16, using a solid copper slug behind a copper/lead point for use as a barrier blind round. The bronze tip might end up being better in the long run, but that 13% chamber pressure increase gives me the heebie-jeebies.

This is typical US Army thinking... we'll just test it in the field.