My 2 credits...
FWIW - based on almost 30 years doing this stuff professionally, between military and law enforcement, and to include 2-way range experience both overseas and stateside. Also being a "certified" firearms instructor for a large chunk of that time.
Going to ramble a bit here. Just a few thoughts from where the threat has touched points:
- The early 20th century study cited had some valid points BUT there are important elements to keep in mind. The first being, the vast majority of the rounds looked at in that time were based on the "big bullet/slower velocity" school of thought, and using older powders and technologies; to include in general solid/soft point lead rounds. Technology has come a LONG way in ammunition - heck, even the past decade has seen some interesting advances. So, while it's a starting point, you would be better served looking at more current data such as comes out of the FBI at Quantico and the USMC/US Army ammunition evaluations which have taken place over the past few years. The modern school of thought in rifles seems to find the peak of effectiveness at somewhere around the 6mm (+/- 1mm) diameter range, working at about 700-1000m/s velocity... there are of course debates within and around this, but these numbers seem to provide a relatively consistent end result without overpenetration, and while allowing your troops to carry a reasonable amount of ammunition. Pistols have a bit more debate, BUT, with modern ammuntion (expanding jacketed hollow point/bonded variations) seem to really be about the same in terms of real world results. I can state similar experience in my time - there are VERY few "one shot stops" with a handgun round, unless a central nervous system hit is involved & for all the arguments people get into, I've seen very few people get up and argue back after a few rounds of 9mm in the face. HOWEVER, I can also say, that if it ISN'T one of those CNS or artery hits, most handgun hits are pretty survivable with modern technology.
- Traveller (particularly CT, my original and still preferred) pretty much followed these lines for ammo - or, looked at some "newer" technologies (lasers, Gauss weapons using a small diameter but super high velocity projectile, plasma, etc). Surprisingly it seems that little was done in terms of weapons tech/ammunition etc. Moving a projectile into soft tissue to cause damage is a pretty simple concept, so I tailor my "what if" advances to things like caseless/binary ammunition, and the like in my games, and higher capacities than in the stock rules.
- Sure, sepsis, infection, fragments remaining behind and the like can be an issue. BUT we are way further along with this in 2017 than we were even in 1970... injuries that would have been considered a death sentence in 1917 are a routine treatment issue these days. So, we can only expect similar advances in the time between now and reliable star travel...
- I will qualify that, and kind of follow on the points people were making about arterial hits, bone shattering etc. - yeah, it can all be a pain (literally)... While as I said, if you survive the initial contact, most gunshot wounds are survivable these days - it's not a quick or painless recovery. Whether surgery, rehabilitation, or loss of sensation/function, there is definitely a path to healing. How crunchy you choose to make that in game is your call...
- Without turning this into a marksmanship lesson, there are two reasons we generally teach to aim "center mass" (really center of *visible* mass to be accurate) - #1, greater chance of hitting those vital organs or nervous system elements to incapacitate your target rapidly; #2, greater margin for error. If I'm aiming at your head/hand/leg and miss by six inches who knows where the round goes... if I'm aiming at your bipedal sternum and I'm off by six inches it's still in your body somewhere. Also, as sexy and effective as they are, head shots on a moving target when you're moving, under stress, and the like are gorram hard... the folks who do that stuff for a living spend enough time to have skill levels well above average.
- Now for game thoughts. As I've stated another time, "back in the day" I debated weapons and ammo mechanics with the best of them. I'd fight for that extra +1 because the "Rhydellian ACR is known for the reliability and lethality, so *of course* Imperial Marine Commandos would use it first!" Now? We're working on a 2d6 range... a +/-1 is a way bigger influence than any of these factors really should be showing. If you want to go that route, I am not knocking it - but I prefer to let players use that for flavor text more than worrying about how it influences the actual rolls.
- Same general theory on skills. IMTU I pretty much put a skill level 0 at "ok, but not super-experienced or used to performing under stress", level 1 is a "I could get a job doing this", level 2-3 is "I can teach this"; and 3-4+ is "I'm well known for my ability at this". Since I typically cap out terms and levels, I don't usually see higher numbers. So, IMTU, GC-0 is "I know how to operate and use the weapon in basic situations, but don't have a ton of combat experience," level 1 is infantry competence with probably at least some real-world time, and 3+ is considered *good* and known for their ability. I also group my weapons together, rather than the "I have a level 1 in ACR and a level 2 in handgun, but you give me a regular rifle and I'm -3" - always struck me as stupid, given that you're just applying different basics to tools in the tool box.
Think I'll wrap it up there. On a side note, for the guys having issues with anticipating recoil and double action/single action transitions I can give side pointers if you want
