Shouldn't the damage inflicted by firearms be fixed?

[DouglasCole]

Originally Posted by Johnny Angel

All of that aside. I think there are reasons to justify still rolling dice for gunshots. Furthermore, in my opinion, for someone who wants to use fixed values to change dice values into fixed values than it is to change fixed values into dice values.

The reason I like armor as dice is it lets you subtract the armor and then roll the remainder.

The other thing you can do to get much more variable results, although less satisfying due to fewer dice, is only roll one die, and use multipliers. So if you have a 7d attack against DR10 (3d) armor, you roll 1dx4, which will give the minimum 4 and the maximum 24 much more often than rolling 4d, which only has a 1 in 1300 chance of max damage instead of 1 in 6.

[Ragitsu]

Does damage versus objects work the same way (random damage) in 'real life'?

[RyanW]

Originally Posted by DouglasCole

The reason I like armor as dice is it lets you subtract the armor and then roll the remainder.

The other thing you can do to get much more variable results, although less satisfying due to fewer dice, is only roll one die, and use multipliers. So if you have a 7d attack against DR10 (3d) armor, you roll 1dx4, which will give the minimum 4 and the maximum 24 much more often than rolling 4d, which only has a 1 in 1300 chance of max damage instead of 1 in 6.

Is there a post that has all of your gun damage house rules together?

[RyanW]

Originally Posted by Ragitsu

Does damage versus objects work the same way (random damage) in 'real life'?

Versus any kind of complicated object, yes. Shooting, for example, a car might destroy a critical portion of the frame. Alternately, it might put a couple of quarter inch holes in sheet metal and not touch anything else.

[Johnny Angel]

Originally Posted by DouglasCole

The reason I like armor as dice is it lets you subtract the armor and then roll the remainder.

The other thing you can do to get much more variable results, although less satisfying due to fewer dice, is only roll one die, and use multipliers. So if you have a 7d attack against DR10 (3d) armor, you roll 1dx4, which will give the minimum 4 and the maximum 24 much more often than rolling 4d, which only has a 1 in 1300 chance of max damage instead of 1 in 6.

I'm not very familiar with the GURPS rules yet, so I really can't offer much comment on that.

I read the wiki article on hydrostatic shock. The way in which it was explained to me during my time with the military is a lot different from how the term is used in the article.

How would you use armor as dice? Honestly, I'm not familiar with the concept at all. Coming from a D&D background, I'm accustomed to everything simply being a fixed number.

On the topic of shooting objects: If you look at some of the older military radios, they actually have a small bullseye on them which is meant to show you where to shoot the radio so that you can destroy it in such a way that the enemy can't recover any information from it. I'm unsure if the newer models do. Anyway, the point is that you may or may not be able to disable the radio by simply just shooting it. Even if you did disable it, there may be enough of the internal components left to rebuild the radio and gather information from it.

[SuedodeuS]

To use Armor as Dice, convert the DR to a dice value by dividing by 3.5 (so DR 14 becomes 4d, for example). You then subtract this value from the damage of your weapon. So, an AK-47 against DR 14 armor would actually deal 1d+1, rather than 5d+1-14. Basically, you subtract out the DR before rolling damage, rather than after the fact. I think I saw somewhere that if the weapon and armor use the same number of dice (so that DR 14 - 4d - armor against a SCAR-L - 4d+2), you consider the two dice to cancel out to 1d-4, then apply anything left over. So, in the case of the DR 14 armor versus a SCAR-L, the SCAR-L deals 1d-2 penetrating damage.

EDIT: Found the post explaining it, by DouglasCole (who I assume is the one that came up with it). See it here.

[Gizensha]

Originally Posted by Johnny Angel

How would you use armor as dice? Honestly, I'm not familiar with the concept at all. Coming from a D&D background, I'm accustomed to everything simply being a fixed number.

I presume it's figured the same way as the adds to dice conversion optional rule that I seem to recall isn't recommended and can't find where it is in the books right now - each 7 armor is another two dice removed, the in between levels being removed on either 3 or 4, forget which.

[DouglasCole]

Originally Posted by RyanW

Is there a post that has all of your gun damage house rules together?

Well, there was my Pyramid article, where I did a bunch of them together. Some of them aren't exactly house rules anymore, others are.

In general, things I like and find realistic:

1) Blowthrough

By and large, this is a concept that works for me, but it must be used in concert with the more-complicated bleeding rules. GURPS does what I like to call "net present value" damage, which is to front-load the effects of structural damage and bleeding into one die roll. This is a perfectly gameable decision, and has a lot of merit.

However, for simulationists, it tends to produce a lot of one-hit stops and kills (which isn't necessarily a problem) in a one-second timeframe (which is).

I like to apply blow-through, modified for target severity (so no limit on Brain, blow-through on HPx3 for vitals). I also apply all modifiers multiplicatively to damage before blow-through to find bleed frequency. So a hollowpoint (x1.5) shot to the vitals (x3) with a 2d+2 pi+ weapon that does 9 pts of rolled damage to a 10HP target will do:

9 x 3(vitals) x 1.5 (hollowpoint) x 1.5 (bullet size) = 60pts of damage. This will blow through after 30 (HPx3), but will bleed for 1pt for 5pts of unsubtracted damage, or 1hp per every (60pts / 5 = ) 12 seconds.

There should be a penalty on the HT roll for stopping the bleeding (-1 per multiple of HP) so that's -6, which is also applied to First Aid rolls, or half of that to Surgery.

2. Armor as dice

Against firearms, I like to convert armor from DR in points to DR as dice in a 1 for every 3.5pts of DR, drop fractions, way.

Two methods: (a) subtract armor dice from weapon dice; if the result is negative, there's no penetration, although for every 2d stopped you have 1pt potential blunt trauma damage. (b) the other way is to subtract in quadrature, which is annoying but reasonably accurate, as it simulates the armor taking energy out of the projectile better than straight subtraction.

In either case, if there's more damage than armor, roll the remainder as a wound.

3. Increasingly variable damage

Bullets can glance off, or they can do inordinate damage; sometimes the results on real people seem almost disturbingly random. So instead or rolling oodles of dice, just roll one, and multiply that by the number of dice in the attack. So an M16 might do 5x1d instead of 5d.

[AmesJainchill]

Originally Posted by DouglasCole

(b) the other way is to subtract in quadrature, which is annoying but reasonably accurate, as it simulates the armor taking energy out of the projectile better than straight subtraction.

Um, I wiki-ed quadrature, but that didn't help...what are you making square?

[lwcamp]

Originally Posted by AmesJainchill

Um, I wiki-ed quadrature, but that didn't help...what are you making square?

Damage in GURPS scales as the square root of the energy. Armor subtracts from the energy. Thus, a 5.56 NATO round that delivers 5d might have 5*5 "points" of kinetic energy, or 25 points. Armor rated at 4d would subtract 4*4 = 16 points of energy from the bullet. This leaves you with 9 points of energy. Now take the square root of this to get dice that go through armor to injure whoever is on the other side (3d in this case).

Taking a square root in a game during combat would be quite annoying, I imagine (although I can't say for sure, never having needed to do it myself). Further, it doesn't always come out so neatly - 2d of armor against that 5d round would call for calculating SQRT(5*5-2*2) = SQRT(21) = 4.5826 (approximately), or about 4d+2.

Luke