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weswood
03-11-2009, 08:58 PM
I've got a couple questions for the demo experts out there.

1- If you taped a lit road flare to a bottle of propane and shot the bottle, would it really blow up, ala Dawn of the Dead?

2- If a pinch of C-4 or other plastique was put in a muzzle loading rifle, would it blow up or not? Not a big piece, maybe as big as the last knuckle of a little finger. I'm thinking it would act like a very quick burning powder, push the projectile out. I'm thinking a .45 octagon barrel about 1" across the outside.

3- Would a tracer ignite gas in a vehicles tank? Civilian car or truck.

Enquiring minds want to know, some explanation would be nice- like the propane bottle wouldn't blow because the pressure coming out of the hole would keep the flame away from the biggest part, sort of like a bunsen burner.

Legbreaker
03-11-2009, 09:20 PM
Good questions all.

1. Not too sure, but I doubt it. I'm guessing it might ignite the escaping gas and create a jet of flaming propane.
Mythbusters did a few experiements on this a while back but using bullets rather than flares - they ended up having to use incendiaries I believe.

2. Using HE as the propellant? You've got some serious issues. HE, unlike low explosives such as gunpowder, tend to detonate so fast they shatter materials. Low explosives detonate or burn much slower and so have a pushing effect (this is why they're good propellants).
You try using HE as a propellant and you've at best destroyed your weapon, at worst killed yourself with flying ex firearm shrapnel.

3. Possibly - Once again, Mythbusters (Damn they do some cool experiements) have been there and tried that. Normal bullets wouldn't have a hope. Hitting below the level of the fuel, also no hope. The round needs to travel through the gaseous fumes at the top of the tank to have a chance.

Targan
03-11-2009, 09:43 PM
I agree with everything Legbreaker said. I would add that to set off the C-4 you'd need some form of detonator or priming explosion but black powder or smokeless powder might do the trick (even though both are low explosives). What Leggie said about HE shattering materials is correct. Depends on how much C-4 was used but I'd say the gun would suffer a catastrophic failure somewhere inside.

jester
03-11-2009, 10:12 PM
Propane tank and flares, nope, it would burn for a while, the gas inside would boil, the steal would weaken and the tank would either burn out or split where the tank had been compromised.

C-4 working as a propellant, sure but not in the type of barrel you have in mind. And I would not put that much C-4 nor would I use a "barrel" that narrow, and I wouldn't pack the charged either. Something like a larger canon barrel you could get the desired effect of basicaly a directional blast. My question is, if you have the C-4, why not just make a claymore, it would be easier and safer.

Tracers igniting gasoline, it can. Remember tracers have different ballistics than a normal round. If the gass is leaking sure, if the round lodges in the tank sure. I have seen tacers loose their jackets on the range and bounce all over. So that is what I would thinkk would do it, a peice of the burning jacket would come off and that is what would ignite the fuel.

Targan
03-11-2009, 10:17 PM
My question is, if you have the C-4, why not just make a claymore, it would be easier and safer.
Excellent point.

Legbreaker
03-11-2009, 11:38 PM
mmmmmm, directional mines.

Yum!


Why not simply make your own blackpowder? It's not exactly rocket science and it's what most muzzle loaders are designed for anyway.

Grimace
03-11-2009, 11:38 PM
Basically what people have said it pretty much true. There is a small chance that with the flare and the punctured propane tank that you could have a "jet propelled" tank until the pressure escaped enough to stop it moving. But you're not going to have a big explosion or anything.

Also, a note on the C4. It *might* not ignite from black powder. It would depend on how much you packed in. If it did ignite, like was mentioned...*pow*, ruined weapon and you're likely picking shrapnel out of your face if you survive.

Finally tracers... yes, they can, but not every time guaranteed. You'd probably have to put more than just one into a gas tank to get it to ignite.

Eddie
03-12-2009, 12:23 AM
I'll add on the C4, you need two things to ignite it, heat and pressure. A muzzle loading rifle would provide the spark from its striker, but not any pressure using the C4 as a powder alone (if that's what you're meaning).

Now if you use black powder as a starter, it would provide enough of both to ignite the C4, at which point, it's going to burn at 28,800+ fps, which is going to seriously damage your chamber, barrel, and most likely your upper torso and head.

weswood
03-12-2009, 06:22 AM
Cool. Thanks for the info. I've had some very basic training with demo, not nearly enough though.

On the C-4 question, I can see that it wouldn't explode due to no pressure, but a spark should ignite the C-4, correct? Would a chunck of burning C-4 provide enough gas to push the bullet down the barrel?

As far as making black powder or a directional mine, I have nothing specific in mind, just curious.

Targan
03-12-2009, 06:32 AM
A spark won't ignite C-4.

Legbreaker
03-12-2009, 06:34 AM
Now if you use black powder as a starter, it would provide enough of both to ignite the C4, at which point, it's going to burn at 28,800+ fps...
That's 8.7 kilometres per second kiddies, or 31,601 kph (19,636 mph).

To put if into a little more perspective, the muzzle velocity of an M60 machinegun, that is the speed the projectile is travelling as it leaves the barrel, is just 840 metres per second (3,024 kph/1,879 mph)

I think it's farily obvious just why HE isn't much good as a propellant when you look at it like that.

pmulcahy11b
03-12-2009, 08:04 AM
Cool. Thanks for the info. I've had some very basic training with demo, not nearly enough though.

On the C-4 question, I can see that it wouldn't explode due to no pressure, but a spark should ignite the C-4, correct? Would a chunck of burning C-4 provide enough gas to push the bullet down the barrel?

As far as making black powder or a directional mine, I have nothing specific in mind, just curious.

C4 will burn, but without pressure to boot, that's all it will do. (You can actually use a small chunk of C4 to heat up your rations.) That's why you need a blasting cap or something like that. A spark from something like a flintlock or even an inline won't even start C4 on fire. A wick might, but since it will just catch on fire (maybe), there's no real point for the purpose you have in mind.

As for a blackpowder mine -- they've been used throughout history, including by the Chinese as early as (IIRC) 300 AD. The Ninja of Japan used them; the Turks used them, various Arabic countries used them, and eventually they made their way to Europe. The Chinese and Ninja even had pressure detonators for them.

I don't know if one can make an improvised blackpowder directional mine, but with C4 it's easy. You just need a strong backplate, a bunch of metal fragments or rocks for the fragments of the mine, knead them into the C4, then wrap it in plastic or cloth and stick a blasting cap into it. Shove some sticks into the C4 at the bottom to make legs, or just prop it up on something. That's a trick the Viet Cong taught the US military, and I was taught that one in the Army (much later, of course).

Legbreaker
03-12-2009, 08:24 AM
Made myself a stick mine with barbed wire (similar to a POMZ), claymore and "danert bomb" (reel of barbed wire stuffed full of about a dozen sticks of plastic - roughly 10 lbs) back on my initial explosives course.

Oh what fun! :D

But any fool can make a big bang. I prefer precision charges - cutting your name into sheet steel for example. Too little and you barely knock the rust off, too much and, well, I think you can imagine.