Weapon damage in BattleTech roleplaying

The way damage is handled in the Classic BattleTech RPG is much more detailed than what is usually presented in Total Warfare, with a variety of additional rules and features which would be relevant for an individual character basis, but would be impossibly difficult to keep track of for large scale conflicts, involving multiple platoons of infantry. However, for cases where the combat involves few individuals, then this scale is more viable. This article focuses on the RPG system of measuring damage that individual infantry weapons can deal.

Damage Codes
Weapon manufacturers measure the potency of their weapons against the BAR rating of whatever is being shot at, and how much damage the weapon does as a result of that shot to the body of the target, if the shot penetrates (note, the term penetrate is a very loose term, lasers melt things, and grenades explode things). Overpenetration does not increase the damage a weapon deals.

The codes are written out as:

Armor penetration, Penetration type against BAR/Base damage upon full penetration, Special notes

Or, for example, in the case of a Man-Portable Flamer:

3E/5CS

The damage codes on the armor piercing side (the left side of the "fraction") is covered under Barrier Armor Rating the first letter of the AP code is what type of damage the weapon penetrates the enemy BAR with. In this case, the flamer will work unfettered through BAR 3 energy resistant armor and below. The damage code on the base damage side (the right side of the "fraction") is how much "body damage" the weapons deals to the average individual in the event the shot fully penetrated the BAR of the target. The number is the "base damage" applied to the individual. In this case, the weapon deals 5 base "body damage" to the victim. Any additional lettering after the base damage is an additional effect the weapon may have against the target. In the case of our flamer above, the weapon deals "continuous damage", as reflected by the "C", as well as "splash damage" as contacted by the "S" as should now be obvious, considering the weapon in question is a flamethrower.

Basic Type Codes are as follows:


 * M = Melee: Melee weapons of all types, blades, blunt, or even hand to hand "weapons" such as an individual's fists count here.
 * B = Ballistic: Things that shoot a solid at a target. This could be a Needler Pistol or an Elephant Gun.
 * E = Energy: Energy weapons, such as laser rifles and the Support PPC, as well as heat based weapons, like plasma rifles.
 * X = Explosive: Explosive ordnance, such as grenades and artillery. See the Universal Ordnance Rating Standard.
 * S = Special: Specific edge cases, like Stun Grenades, Flashbangs, and gasses, as well as hostile environments.

Extra damage codes are as follows:


 * A = Area of effect: Common to explosives, but can also apply to certain other types of weapons. This is relatively uncommon to see, and in most cases, won't be seen on this wiki. Instead, refer to the Universal Ordnance Rating Standard. Damage with this code assigned has damage dropoff, but can hit multiple individuals.
 * B = Burst Fire: Implies the weapon can be fired in bursts of more than one shot. Deals increased damage based on accuracy of the burst, by one point per "margin of success". Well placed, single shots often can deal more damage, but usually not as much as burst damage weapons. A well placed single shot does fractional additional body damage (rounded normally), compared to full digit additional body damage of burst fire mode weapons.
 * C = Continuous Damage: Usually caused by environmental effects, such as fire, acids, toxins, atmospheric taints in general, and a variety of other reasons. This type of damage will continue unless something happens to stop it.
 * D = Subduing/Disabling: These types of weapons do not "injure" the target (or they aren't intended to). These weapons apply "fatigue damage" in an effort to knock out, or subdue the target. This generally applies to things like Stunsticks or stun grenades, as well as tear gas.
 * D* = Direct Damage: Any damage denoted with a D* is direct, unblockable damage, generally caused by extreme local circumstances, such as being within a vehicle suffering an ammo explosion, or sitting in an overheated vehicle.
 * S = Splash: These weapons "splash" around the intended target, usually used on flamers or plasma guns, as well as flechette weapons, giving an easier time to at minimum hit something.

Alternative Ammunition
Most weapons can take some form of alternative ammo, such as Frangible Ammo. These ammo types can be loaded into weapons and modify the characteristics of the damage applied as a result of a hit, or confer some sort of other additional benefit, such as it being easier to lead a shot using Tracer Ammo.

In the case mentioned above, Frangible Ammo does -1B/0 to the characteristics of the weapon, implying that it will do 1 point less ballistic penetration versus personal armor, while not hampering damage (though this ammo has a special feature to not penetrate solid surfaces, like walls).

Note
It is worth mentioning that, if individuals were being shot at by vehicular scale weapons, they all have an AP of 10, and their damage to an individual infantryman is equivalent to six times their Total Warfare numerical value. So, an AC/20 hitting a trooper in the chest has a RPG damage value of 10B/120, something nobody is going to walk away from. It could be possible for a particularly lucky individual to survive a single LRM hit though, as that would have a 10X/6 damage value, though they will probably lose a limb as a result.

Different body parts also take different amounts of "base damage". Less "critical" parts of the body being hit can reduce the overall "body damage" taken by a hit from weapons. The head for example takes double the base damage after all other modifiers, while the arm or leg takes three quarters the damage.