Since people have been poting their own armor rules here is the Iridium System, my rules.

Armor is split into ten areas and may be mixed or matched. Armor is ablative and protects for a given amount. Defense is a separate target on a d20 that your opponent must roll at or above. Defense is based on (STR+CON+AGL)/3. Heavier armor decreases your Defense making you easier to hit. Higher STR offsets this reduction. You are able to direct your shot to a location, after a successful hit, via a Targeting skill check. Critical on a natural 20 and fumbles on a 1.

Guess that was the combat system but I think it helps put armor in context.

Bill

Dangerous Journeys?

Roll location (non-vital, vital, super-vital, ultra-vital), determine damage, subtract armor. Damage remaining subtracted from Physical Trait.

7 different attack forms, protection varies between each. Some types of armor provide no protection at all against some attack forms. Metal armor actually increases damage caused by electrical attacks. Most armor does not protect against attacks on all locations. Plate with all the fixins is the best.

BTW: Broadsword 4d6 damage (cutting). Mace 3d6 damage (blunt). Chain 15 points protection (cutting), 5 points protection (blunt).

I tihnk the trouble is that armor isn't nearly a universal enough thing to warrant a universal mechanic.  Different types of armor protect in different ways.  Some armor is designed to deflect, making armor as AC bonus make more sense, while other armor is designed largely to absorb and lessen damage, meaning armor as DR makes more sense.

It's such a wildly varyign thing that it's rather tough, to me, to really pin it down to a universal mechanic, unless you narrow the field.  

My own game takes place primarily at a modern-ish tech leve in terms of armor, so there's not much liable to be floating around beyond leather, salvaged kevlar, and the bigass powersuits of the big bad guys, all of which work by absorbing and stopping the damage.  With a kevlar vest, you aren't less likely to be hit solidly, it's just that when you do get hit, the armor absorbs the blow so you don't wind up dead.  So in that sense, I think armor as DR is great.  

But for a more medieval setting, things get complicated, because you're goign to have a lot of both runnign around.  I think plate armor works better as an AC bonus than DR, because it's designed more to turn the blow of the sword with sharp angles.  A good thrust though will go right through and skewer the guy inside.  Chainmail sort of does both deflect annd absorb depending on how you look at it.  

It's damn annoying for universal systems, 'cause it means you end up with stuff like the complicated mess that is the full GURPS armor rules.

Quote from: MarcoJAGS does this. When armor is hit by a penetrating attack it gets an "armor save" to convert the damage to Impact (far less severe). Some of that damage may or may not get through but if your bulletproof vest makes its save you're probably just slightly bruised instead of badly bleeding.

-Marco

Gurps 4e has rules for flexible armor that covers 'blunt trauma' in that for exery like 10 points of kinetic damage flexible armor takes, you take one point of damage from blunt trauam assuming the armor completely stopped the damage. if even one point gets thru the armor, you take no blunt trauma.

Traveller 4 had a rule for flexible armor to convery dice of damage into single points of damage to represent blunt trauma.

Common sense is needed here, of course. A laser type weapon won't do anything like this, whereas a baseball bat or sledgehammer will do more of it, it's all down to common sense.

Another way to do this is to have the armor rated for penetration resistance and absorbption. The penetration resistanct stops the bullet from getting thru the armor, the absorbption factor represents how well the secondary impact is absorbed. So a classic knight would have his plaets as the penetration resistance while the quilted padding under it represented the absorbing properties of his armor.

I have armor reduce damage.

Another damage reduction guy, but I'll go into why.  It's important for me to be able to parse the results of the rules into narrative.  That is, I want to know if he missed or his blow was deflected by your shield.  This makes the game feel more interactive and immersive to me.  It's also why if a game MUST have dumbass inflating hit points I want some kind of VP/WP split.  I can deal with it being both luck/ability to avoid and how much punishment you can take.  I just want to know which a given blow is.

In classic unisystem, I'd have the armor wearer still take half the damage in Endurance.  Getting shot can still put you down or even unconscious.  Works pretty well.

If you want detailed armor rules, you can always look to Battlelords of the 23rd century. Less detailed, you can go with SLA industries, where armor stops damage, but weapons have an AP stat that is essentially bonus damage to peirce armor only, and an Armor DAMAGE stat (with armor having it's own HP...)  

Both games generally involved the same concept re:armor, one was a bit lighter than the other.

Me? I'm all for faster combats. No hit locations, etc. On the other hand, armor as AC is just one step to far in abstracting. It ruins my 'immersion' and my 'narrative' and even my 'logic... er... gaming'.  DR (say it again... DR), in your mechanism of choice.

That is: many of the cited armor rules are variations on reducing damage.  Make what you will of it.

So any suggestions as to DR for armor in D&D3.5? Or is it just a lost cause?

d20 Modern and d210 Future might work as models. You'll definitely want a class based armor bonus if you want to avoid people always getting hit all the time. It might need a really major change though, as the BAB system in 3.5 is designed with penetrating armor in mind.

Take a look at the various feats that made it into games like Babylon 5, d20 Modern, etc. Some feats went away, and quite a lot were changed. While it might not have been all because of the armor change, some probably were.

QuoteDR (say it again... DR), is your mechanism of choice.

Thanks for all the input so far.  I've gone back to the rules and updated the section on armour to use my own take on Damage Reduction instead of the old school Armour Class.  Like Spike and Maddman said -- this seems better for taking the stats / dice / results and turning them into interesting narrative.