“Realistic” d20 Firearms

Calls for “more realistic firearms” are fairly common in d20.

That usually (albeit not always) seems to mean “we think they should be a lot more powerful!”.

Now it’s true that modern guns have several advantages over things like slings, bows, and crossbows.

• They supply their own energy. It took many years of constant practice to train a longbowman. Kids, elders, and those with crippling injuries need not apply. Crossbows could be used – but they were heavy and would take far longer for a child, elder, or disabled individual to cock (often with a windlass) if they could manage it at all.
• They are very easy to use. Bullets may drop, and be affected by the wind – but they are considerably faster and denser than bolts or sling stones and such, and so it’s less of a problem. Point-and-pull-the-trigger lets you train a tolerably competent combatant very quickly indeed. This also means that a lot of people manage to accidentally shoot themselves or others since they may be able to use their gun but they aren’t necessarily good at it.
• Bullets tend to expend on impact, and may tumble and/or fragment, causing more tissue damage along their path. They can also cause hydrostatic shock, damaging adjacent tissue that isn’t actually hit. Of course, that doesn’t always happen to any great degree. For the sake of comparison, actual war ammunition for bows and such – things like broadhead arrows, serrated edges, barbs, and so on – can substantially increase the amount of tissue damage inflicted by bolts and arrows and such, as well as making them considerably more difficult to remove.
• Bullets don’t plug up the holes they make, making it a lot easier for the victim to bleed out.

All of which is lovely theory, but what does it actually mean in terms of real results?

• Emergency room reports suggest that the chance of a single bullet proving lethal – generally by hitting something vital – is about 20% because about 80% of the individual gunshot cases pull through. Presuming that that number is close enough for gaming purposes… if you’re shot once, there’s an 80% chance of survival, five times gives you a one in three chance of survival, and ten times gives you just under an 11% chance or survival. Sure, there might be overlapping injuries that matter less, or interacting injuries that matter more, but for out purposes we can disregard that. We are talking about games, not about a surgical training course.

This is what fully automatic weapons are all about; a burst of bullets offers a better chance of at least one hitting, can target a group, and – if more than one hits a particular target – greatly improves the chances of a kill.

Getting similar statistics for – say – knife wounds is virtually impossible. That’s because guns supply their own energy; being shot accidentally is very little different from a serious attempt to kill. With knives… you get a lot of slashed fingers and extremities from kitchen knives, people drop them and stab themselves in the foot, you get minor defensive wounds from attempts to block, parry, or dodge, and lots of similar noise in the data. The reports don’t reliably distinguish between “knife wound from an actual combat knife that someone was putting a reasonable amount of strength behind in a serious effort to kill” and “backed into a paring knife that got left on the kitchen counter and now it’s stuck in my buttock”.

My fairly casual attempt to sift through that mess suggests (albeit certainly does not prove) that actual “tried to kill you” single knife wounds have something like an 85% to 90% survival rate.

On individual terms (“I’ve” been stabbed!) that is not that big an advantage, but statistically (a lot of people have been stabbed!), and when you’re considering multiple wounds, it can have a substantial impact. If it’s an 85% survival chance instead of a mere 80% then your survival rate for five and ten hits goes from 33% and 11% to 44% and 20%. At 90% chance of survival it goes to 59% and 35% – which looks a LOT better doesn’t it?

Still, individual bullet wound survival rates are not really all that different from knife wounds – and are probably even more similar to the survival rates you’d get with swords, axes, crossbow bolts, and arrows, all of which are generally nastier than knives. Sadly, those are so rare these days that meaningful statistics are almost impossible to come by even before trying to separate out the “actual attempt to kill” part.

Now this doesn’t really account for sniper rifles inflicting massive damage – but it doesn’t really account for being hit by a cannonball or hundred-pound trebuchet stone or anti-tank missile either. Individual characters are most often using, and facing, hand weapons at relatively short range – not siege or anti-tank weaponry. “Heavy weapons do a lot more damage” really isn’t news to anyone. That’s what heavy weapons are all about.

The real problem with using real injury statistics in a game is, of course, is the fact that real injuries are incredibly diverse and complicated.

A finger-tap – or paintball shot, or hit from a baseball – to the right spot on the chest that occurs at the right instant of the heartbeat cycle can kill. So can a single be-be, or a cat scratch, or being stabbed with a pencil. It’s just rare.

On the other hand. people have survived falling several stories and being impaled on multiple lengths of rebar. They’ve survived getting crowbars through their brains. If cold enough they’ve survived lengthy periods without their hearts beating. They’ve survived throwing themselves on top of two WWII fragmentation grenades at the same time. They’ve survived taking nearly thirty bullets. They’ve survived being dragged through a hole five inches across. They have a roughly one-in-three chance (with modern medical care) of surviving being stabbed in the heart.

But, once again, it’s pretty rare. When that sort of thing happens to them, people usually die.

To even come close to representing this in a game, you’ll want a hit location chart, with each location given a semi-random subchart with a wide variety of injuries on it – ranging from bruising, minor cuts, and flesh wounds with little or no actual effect on up through long-term crippling injuries, possibly fatal injuries (with their own rules), slowly fatal injuries, swiftly fatal injuries, and dead. Give more damaging weapons a better chance to roll the nastier injuries, and really lousy ones (like pencils) a penalty towards rolling the minor stuff. That means that you’ll want to go with a fancy critical hit system, or a system of resistance rolls, or a location-and-injury chart like I used for Baba Yaga. This way there will be a substantial chance that any character who gets into a serious fight will abruptly die.

That’s fine in Baba Yaga, where WWII combat is supposed to be fast, extremely deadly, and to be avoided if at all possible.

The trouble is that – if you want a game to rely on combat for excitement – that’s exactly what you don’t want. You’ll want a system for tracking wounds that’s hopelessly unrealistic and easily survivable. You’ll also want to stay away from long-term crippling injuries and you’ll want it easy to gauge how long you can last in a fight, so that the characters will know when to fall back. There is a REASON why so many games default to some variety of “hit points” or “wound track”. But, if you do that, you’ve abandoned any pretense of “realism” right there. Real people do not have “hit points”. They have messy, incredibly complicated, biology instead.

So no. You CANNOT put “realistic firearms” into d20 without a total rewrite of the combat rules that will make the game unplayable as heroic fantasy.

What, you still want “realism”? Well… OK. It’s just going to have to be “realism” within the d20 framework of hit points and other weapons.

Hm… “Does more damage along the path” and “leaves an open wound to bleed out” sounds familiar. That’s basic Roman-style Shortsword use: stab, twist to increase the damage and bleeding, and pull out. True, bullets do more damage in proportion to their size – but the sword is a LOT bigger.

And that gives us a benchmark that translates into “hit point” terms for d20 games. Handguns…

• Don’t depend on personal strength.
• Do about as much damage as a properly-wielded shortsword. Light ones do a bit less, heavy ones a bit more. Ergo, low-caliber firearms do 1d4, medium calibers d0 1d6, and large calibers do 1d8. A shortsword threatens a x2 critial hit on a 19-20. Livening that up a bit… for low calibers it’s 20/x3, for medium and large calibers it/s 19-20/x2. For shotguns and rifles it’s 20/x3. In any case, a critical hit from a firearm can often instantly kill a “normal” (1-4 HP) person.
• Don’t require any special skill or proficiency to use. Yes, a true expert will be better – but you can learn to use a small arm reasonably effectively in a fight a LOT faster than you can learn to use a sword or bow reasonably effectively in a fight. Ergo, no proficiency is required to use a small arm. If you want to take a proficiency in the things… it costs one Feat or 6 CP and provides a +3 to your BAB while wielding one. (+1 to BAB, Specialized and Corrupted/only for ranged attacks, only for small arms) for triple effect, 6 CP).
• Revolvers and Semi-Automatic weapons can fire quite quickly, allowing for extra attacks even with little skill. Given d20’s time scales… call it +2 attacks at full BAB for lighter guns (a bit less damage than a shortsword), +1 for medium guns (the same damage), and no extras for heavy handguns, shotguns, and other heavier items. If you want to eliminate that from consideration… you’ll probably want to upgrade the damage to compensate.
• Fully Automatic weapons can spray bullets across an area if you wave them wildly, try to hit several targets in a group if you wave them but less wildly, and try to hit a single target several times if you hold them steady. Once again… that’s not really that complicated. Guns still hold the “that’s EASY!” edge over muscle-powered weapons. So… fully automatic weapons can attack an 20′ radius area (everyone there rolls a DC 12 reflex save to keep their heads down or take one hit), attack everyone in a small, tight, group (one roll at full BAB against everyone in a 5′ radius), or do double damage against a single target.

But wait! Guns penetrate armor better! Shouldn’t they get special bonuses or be touch attacks like they are in Pathfinder?

Do they? Which is more effective against Kevlar – a mace or a bullet? How does mithril handle point impacts? (A hint; anything you say is pure personal fantasy, since mithril does not actually exist and so it’s properties are unknown). Will adamantine ignore any bullet with less penetrating power than it’s 20 hardness? Weren’t some knives designed to slip between the links in chainmail or through chinks in plate armor? Weren’t military picks designed to puncture plate armor? Weren’t late suits of plate armor tested by firing muskets at them? Didn’t soldiers in WWII wear helmets to help against head hits? Isn’t armor capable of deflecting an angled shot that would otherwise miss? Wouldn’t that mean that (just like WWII helmets) that the effect of armor is partially deflection and partially absorbing incoming damage and not really to reduce your chance of being hit? Doesn’t heavy armor make it easier to be pulled off your horse? Isn’t this trying to go back to weapon type versus armor type modifiers? That was a lot more “realistic”, but it got dropped from second and later editions partially because it became impossibly unwieldy as more and more weapons and armor types were added and partially because – once you got into fantasy materials and effects – there was nothing to base it on. Or perhaps we should rewrite combat to give armor separate ratings versus slashing, crushing, and piercing damage?

D20 Armor is a pretty high order abstraction. It’s actual physical properties are purely arbitrary. Is giant spider silk equivalent to kevlar? What are the ballistic properties of force fields? Does magical armor operate by spreading impacts evenly across the surface, by causing incoming attacks to glance away, or though applied solipsism that simply allows the user to reject the reality that he or she has been hit? Who knows?

For a basic game… that +3 BAB for being proficient is plenty. Guns are still far and away better than crossbows if your mage wants a backup weapon or something.

Pathfinder makes guns touch attacks (and gives them slightly better damage and/or critical multipliers) partially to satisfy the crowd that wants them to be the best weapons and partially simply to make them different – and thus to make having them around have a major impact on the game and setting. There isn’t any actual “realism” behind it, but given that the whole thing is entirely arbitrary anyway, why not?:

• If you don’t like it… you can use Eclipse and add another attribute modifier to your Dex-based AC modifier, Specialized for Double Effect (only versus guns, 3 CP for +Att Mod, 6 CP for +2 x Att Mod)), or take Immunity/the armor-penetrating effect of guns (Uncommon, Major, Variable) and keep up to 5/12/30 points of armor and shield based AC against guns for 3/6/9 CP, or any of a wide variety of other tricks, and carry on as always. Sure, you’ll be down a feat – but you can just ignore the effects of fairly modern guns being common if it pleases you, and that’s probably worth it in a game where they are.

So really… given the wide margin of error in the data, the level of abstraction in the d20 rules, and the completely unknown effects of magic, psionics, and your reality-bending power of choice, the existing weapon stats found in d20 modern are probably… a bit too good. The listed damage for them is kind of high. Pathfinder firearms are probably a bit overpowered too – their critical multipliers are kind of high – but they do have that annoying misfire problem to make up for it.

What about more primitive firearms?

Well, they were tricky to load and care for, and they are prone to misfire (and, with the really early ones, to exploding), and they were horribly inaccurate. Even with rifling… sights were crude, the propellant loads were anything but standardized, ignition was a bit iffy, and lower muzzle velocities exaggerated the effects of environmental disturbances. At best, you’d probably only be getting off three or four aimed shots per minute. They’re still cheap and easy to use – but player characters rarely care. Player characters are inhumanly skilled, strong, and fast, and they’re usually rich to boot.

So; L6 Eclipse Longbowman: +4 BAB (24 GP), +3 BAB (Specialized and Corrupted for triple effect / Bows only, 18 CP) = +13 BAB with Bows. Two levels of Rapid Strike (Bows) and Innate Enchantment / Personal Haste gets him to firing at +13/+13/+10/+7/+4/+1. Broadhead Arrows get us to 1d10 base damage. Throw in +4 (Dex), +4 (Martial Art), +2 Competence (Innate Enchantment again, and still room even at the base cost for another boost), Spirit Weapon and Imbuement means never having to worry about being disarmed or ammunition and getting a at least a +1 magical bonus.

OK; we are in no way approaching the limits of the bonuses we can get (how about disregarding range modifiers and an ability to ignore armor to effectively get those touch attacks?), and we’re already firing sixty aimed shots a minute, for at least 1d10 +1 plus possible boosts (a strength bonus to damage at the least), at attack bonuses ranging from +24 for two shots down to +12 for the last one.

Sure, we could stack a lot of those bonuses onto Pathfinder firearms too – but what we’d save in getting to Touch Attacks to match Pathfinder we’d have to spend on getting around the drawbacks from the loading time and misfire chances and not getting a strength bonus to damage.

The point here is pretty simple; once you start stacking weird bonuses, spell effects, and personal abilities onto an attack… the base qualities of any reasonable personal weapon really don’t matter very much any longer. What does matter is that guns use their own power to do damage. That’s GOOD for the weak, the sickly, and the young – thus the old adage that “God Created Men, but Sam Colt Made Them Equal!” – but it’s BAD for those with natural advantages of strength and speed – like most weapon-wielding player characters.

In reality, the advantage of early firearms was that they required little skill or training to use and were still reasonably effective. A trained longbowman was far more effective – but the costs of training and supporting one were enormous and suitable candidates were scarce. Since player characters automatically come with that training and various physical advantages… they’re usually better off with classical weapons if their primary focus is weapons.

Given all this… the Federation-Apocalypse firearm-building rules are probably a bit overpowered – but they are talking about firearms from centuries in the future, which adds yet another layer of pure fiction to their capabilities.