Bullets: Overpenetration, Tumbling, Traveling

[FF_Ninja]

So, in prep for the modern campaign I'm running, I've been pouring over [what I expect to be] one of the more important systems I'll need to be familiar with: gun combat. One particular aspect - round behavior upon impact - has been touched on in various threads and boards, but I feel like there's a disconnect.

So far, just about every thought I've read about rounds has to do with varying damage - I.E. larger caliber rounds doing more "damage" than smaller caliber rounds (which, frankly, I believe is patently false). I've yet to find anyone touch upon the nuances of what a round does after it impacts - other than the general idea which is, "getting shot sucks" (which is patently true).

To further define the issue at hand: small caliber rounds have a tendency to tumble when they impact (resulting in more internal damage) and travel when impacting a bone, as opposed to their larger caliber brethren which generally just over-penetrate. Range is a factor, too: shoot a dude at point-blank with a .308 and it'll tend to make a clean (albeit large) hole front-to-back; the same shot at a more optimal distance would have decelerated a bit already.

I'm envisioning a situation where, say, a Russian agent with a .22LR pistol pops someone dissident the skull (old KGB style), and the round penetrates only the first layer of bone but then proceeds to tumble and travel, turning said dissident's brains into scrambled eggs. A through-and-through shot from a heavier caliber weapon wouldn't do that.

Are there any supplements that deal with these issues? Have any of you run a session where you (or one of your players) felt it important to address the nuances of different caliber ammunition, and at different ranges?

[Boomerang]

What is the advantage in going to that level of detail?

Damage has a random element, it is already possible for a small calibre round to do more damage than a larger calibre. When that happens you have a in game explanation (the larger round passed through without hitting anything important).

This big disadvantage in making combat more detailed is that it slows down considerably.

But if you are determined to add more realism, there was a really great Mythbusters episode where they looked at the penetrating power of different calibre weapons when fired into a pool of water, that you might want to check out.

[FF_Ninja]

Originally Posted by Boomerang

But if you are determined to add more realism, there was a really great Mythbusters episode where they looked at the penetrating power of different calibre weapons when fired into a pool of water, that you might want to check out.

Well, I've got a decent grasp of the kind of damage rounds do when they penetrate. I've observed slow-mos of ballistic gel, read some articles, and even seen a few relevant examples in real life.

I just wasn't sure the discrepancy between ammunition calibers was considered in the game supplements. If it was, I'd sure like to know which one so I can read up on it. :) I find half the interest in loading out a character with a gun is also choosing ammunition and having an idea of what it does.

[Anaraxes]

Calibre maps to the 'p' pluses and minuses. Powder load is energy, which maps to damage. Anything beyond that is really below resolution. It's not like some rounds always tumble and others never do, or that on a hit point scale from 1-50 it's going to make a lot of difference.

For that matter, the experts still argue about the exact means of bullet damage and which sorts are better. (Sure, there's plenty of people with confident assertions on the Internet -- but nobody really knows, and it's not that certain of a topic.)

High-tech has rules for different sorts of ammo. Tactical Shooting goes into a lot of detail. There's also Gun-Fu for the action-movie style of gunplay. There's also a couple of supplements with more gun stats (Pulp Guns, Adventure Guns).

Douglas Cole has a spreadsheet that's good for calculating damage for all sorts of cartridges and weapons that aren't already in a book.

[FF_Ninja]

Thanks! You've been a big help!

[L.J.Steele]

Originally Posted by FF_Ninja

Well, I've got a decent grasp of the kind of damage rounds do when they penetrate. I've observed slow-mos of ballistic gel, read some articles, and even seen a few relevant examples in real life.

If you really want the nasty details of bullet damage, you want to read DiMaio's Gunshot Wounds. There's a new edition out. DiMaio was a leading medical examiner for Texas -- lots of information, including pictures, of exactly what happens when someone gets shot. Not for the squeamish or after a meal. Available from CRC Press, Amazon, possibly your local medical school's library which might let you in for research.

Bullets are random. I've had homicide cases where the victim got shot once with a .22 handgun round that just happened to hit the wrong spot and the victim bled out. I've had assault cases where the victim is the luckiest stiff on the planet -- hit mid-torso between 5-7 times with a medium caliber handgun round and was able to walk/run/drive away to medical help and survive.

[DouglasCole]

Originally Posted by L.J.Steele

If you really want the nasty details of bullet damage, you want to read DiMaio's Gunshot Wounds.

DiMaio, Fackler, MacPherson are the right places to start, definitely. They're not always consistent with each other, because disagreements exist even among experts, but these three are required reading.

[Eukie]

Originally Posted by DouglasCole

DiMaio, Fackler, MacPherson are the right places to start, definitely. They're not always consistent with each other, because disagreements exist even among experts, but these three are required reading.

I've gotten much use out of Kneubuehl's Wound Ballistics: Basics and Applications, which addresses Fackler, MacPherson, and other authors and also gives a thorough treatment of the underlying physics.

[Anthony]

Originally Posted by L.J.Steele

Bullets are random.

Injuries in general are random (or more accurately, are determined by a lot of things that are way below the resolution of the game system and are difficult to control under combat conditions, and not really all that easy to control even under operating room conditions).

[Tomsdad]

Originally Posted by Anthony

Injuries in general are random (or more accurately, are determined by a lot of things that are way below the resolution of the game system and are difficult to control under combat conditions, and not really all that easy to control even under operating room conditions).

I guess that randomness can partly be shown with the dice roll (although even some of those are not random* enough since they are partly designed to model performance against RHA) I've seen a couple of grazing house rules that kind of mitigate this.




*and some are just quirks of the dice and adds system 2d-1 is more random than 1d+2