[mmartin798]

Originally Posted by nuke11

Ok, the problem you have at the moment is the document is based on TNT equivalent of an RE of 1.00. The game uses C4 as it's equivalent for an RE of 1.00 and TNT has an RE of 0.75 in the game.

You will need to adjust all of the formulas from the document accordingly.

The Gurney equations don't care about the RE at all. It only uses the uses the Gurney constant which does not necessarily correlate with RE. Taking the example of making C4 1.00 and TNT 0.75, we would expect TNT to perform at 75% of C4. But that is not the case. C4 has a Gurney constant of 2530 m/s and TNT is 2438 m/s, which makes TNT perform at 96% of C4. The equation in my spreadsheet uses the approximation of the Gurney constant, which is one third of the detonation velocity. For C4 that works out to 8200/3 or 2733 and TNT is 6900/3 or 2300. That makes TNT 84% of C4, which is closer to the 75% you are looking for already.

Originally Posted by nuke11

Doesn't the M67 have a solid steel case that also needs to be taken into account for the fragments? Here is a good website that shows what some of the fragments look like: http://machinesforwar.blogspot.ca/2012/03/m67.html

Some more images of the inside of the case and what the fragments look like: http://www.big-ordnance.com/grenades...CutawayM67.jpg and http://www.big-ordnance.com/grenades/loworderM67.JPG

The M26 is the grenade with a spiral wound wire core: http://img.photobucket.com/albums/v1...ut/OR-034A.jpg

The method of determining fragment size was an approximation intended to simplify the math and make fragments of uniform dimensions that can be directly plugged into the EFactor equation. While we could take the mass of the case and the diameter of the grenade to determine an approximate thickness and then divide the surface area up into the number of fragments to get the area of the face which is more accurate as to what happens with the case of the M67, we are then stuck with fragments that are essentially flat tiles. There is no diameter that we can reasonably put through the EFactor equation as it is shown in the rules. Even though we can calculate the kinetic energy of these flat tile fragments, that is still not enough information to determine the wound generating capability of the fragments. KE alone has been shown time and time again to bot be reliable in wound cavity calculation. The EFactor used in the rules is similar to wound approximation models for significant number to ballistic rounds. So while the wire core is not what happens with an actual M67, it works better for incorporating with the EFactor of other weapons in the game.