7h) Combat -- Wounds

Wounds

On the subject of stopping power

Warning: the following essay deals with a controversial subject, and ultimately takes one side in the debate. This should not be taken as an authority, but is included in order to lay a basis for the game mechanics which follow.

Much has been written on the subject of the mechanics of gunshot wound injury and the relative effectiveness of different calibres and types of ammunition. Many gun journalists expound the theory that kinetic energy (KE) is the key to 'stopping power', and that a rapidly expanding or fragmenting bullet is necessary to ensure all that energy is transferred to the victim and that the round does not 'over-penetrate' and exit the body.

Other (or often the same) writers believe that the large temporary cavity created by bullets impacting at supersonic velocities destroys tissue, or creates a 'hydrostatic' shock wave inside the victim's body which can rupture blood vessels and organs, stop the heart and injure the brain at distances far removed from the actual wound.

'Hydrostatic shock' should not be confused with physiological or psychological shock, which are well-understood processes.

Both kinds of pundit apparently believe that traditional low-velocity, round-nosed bullets which pass right through the human body, of the kind which killed hundreds of thousands of people in the wars of the 19^th and 20^th centuries, are ineffective to the point where being shot with one probably wouldn't even hurt that much.

These theories have become quite popular, but there are problems with both.

The speed freaks' hydrostatic shock theory has very little solid evidence behind it, and is mostly based on anecdotal accounts of game animals instantly dropping dead when shot with very high velocity rifle rounds. There are several problems with this.

One is that the accounts are anecdotal and subjective, and not the result of scientific research. We simply don't know what proportion of animals mortally wounded with high-velocity rifles collapse immediately, and what proportion run for a distance before dying.

Another problem is that we don't know, nor will we ever, whether the animals collapsed because of physiological shock, sudden massive blood loss, or because they were knocked out by a 'hydrostatic shock' to the brain.

Ultimately, hydrostatic shock ceases to hold water when one considers that human (and animal) tissue is very tough and elastic, and can survive hard impacts, squeezing and stretching with few or no lasting effects. If a rapid change in pressure could burst our arteries, it would happen every time our hearts beat.

However, it should be noted that higher-velocity bullets create a wider permanent wound cavity than lower-velocity ones of the same calibre, as the narrow area of very high pressure in front of the slug crushes tissue (and crushing is the action of a bullet on flesh).

Proponents of the KE transfer idea go as far as to say that shot placement (where the bullet hits) matters not – except where the brain and spinal cord is concerned – and that a magic number of 700 joules (500 foot-pounds) of energy, delivered to any part of the body, will 'stop' or incapacitate the victim. By this token, a hollow point bullet which embeds itself in the fatty tissue of an obese man's paunch is more effective than a full metal jacket slug which passes right through his torso and comes out his back.

However, much of the KE of a quickly-mushrooming bullet is not transferred to the victim at all, but rather used to change the shape of the projectile.

Furthermore, small arms simply don't have that much KE. A 7.62mm NATO calibre rifle bullet has a kinetic energy of about 3,500 joules at muzzle velocity. A one-ton car travelling at 10 miles per hour has a KE of 12,500 joules – three and a half times as much – but a hit from the former is much more likely to kill you than a hit from the latter. Similarly, a blow from a police officer's truncheon has more KE than a shot from their handgun.

Kinetic energy is a good way of comparing like with like. The difference in KE between two firearm rounds or two vehicle impacts is a good indicator of their lethality and destructive potential. However, it is not the kinetic energy that kills you, it is the nature of the work that energy does to your body that counts.

Despite what you might have read, bullets (like cutting and trusting weapons) injure and kill by making deep, narrow holes in the human body. The severity of the wound is mainly a question of where the bullet hits (which internal organs are in its path), how deeply it penetrates and how wide a hole it makes. Higher-velocity and higher-calibre bullets are more effective because they make a deeper and wider hole.

'Over-penetration' is not so much a problem, but rather a desirable effect. A bullet that passes right through its victim, leaving a large exit wound, will have more chance of hitting a vital organ than one which comes to rest within the body. Taking into consideration that one may need to shoot through a car door, tree trunk or sandbag wall to hit one's intended victim, we can conclude that the more penetration a weapon has, the better.

The truth is that there are no mysterious physics of wounding, nor can it be boiled down to a mathematical formula. A person shot through the heart or a major blood vessel will pass out from blood loss in less than 15 seconds, and die not long after. A person shot through their thigh muscle might fall over and pass out, or they might not, but they're not going to die of that wound unless it goes untreated and they get gangrene. In science the simplest answer is not always the correct one, but in this case it is.

Firearms are very efficient weapons, much more so than weapons that work by brute kinetic energy alone such as clubs or bombs. A bullet propelled by the tiny amount of explosive in a rifle cartridge has a greater lethal range than a low-yield nuclear weapon.

Firearms have been in use since the 12^th century (in China) and have, when combined with the bayonet, been the universal infantry weapon since the 18^th century. There are good reasons for this. The flintlock musket gave the common peasant or urban labourer the ability to shoot the steel-plated knight off his horse, rendering body armour obsolete until the late 20^th century. The percussion rifles of the mid-19^th century could shoot a lead bullet right through one soldier's body with enough force remaining to kill the man standing behind him. Modern automatic weapons, although largely unchanged since the end of WWII, have many times the fire power, accuracy and range of the first cartridge arms.

In Lead and Chrome, the wounding potential or Damage Class (DC) of different firearms is calculated using a modified version of the formulae developed by author and firearms expert Kevin Dockery in his book Edge of the Sword Volume One: Compendium of Modern Firearms. Edge of the Sword was apparently meant to be a fully-fledged role-playing system, but it never materialised. What the book did contain was a combat system, with formulae to calculate both the penetration of a firearm and the total volume of the wound it creates.

In Lead and Chrome, the results of these formulae are 'crunched' into the PEN and DC numbers. PEN and DC for non-firearms is calculated based on the author's subjective judgements about their likely effectiveness, based where possible on scholarly articles.

Hit Location

Once a character has been shot, stabbed, punched or whatever, we need to find out where they have been hurt. For this we use the hit location table:

Primary Hit Location Additional Hit Locations (for shotguns etc.)

Roll D20: Roll D6:

1: Skull 1-6: face and neck

2: Face and neck 1-3: skull; 4-6: chest

3-4: Chest 1: face/neck; 2: upper R arm; 3: upper L arm, 4: heart; 5-6: abdomen

5: Heart 1-3: chest; 4-6: abdomen

6-8: Abdomen 1-3: chest; 3: heart; 5: upper right leg; 6: upper left leg

9: Upper right arm 1-3: chest; 4-6: lower right arm

10: Lower R arm/hand* 1-3: upper right arm; 4-6: abdomen

11: Upper left arm 1-3: chest; 4-6: lower left arm

12: lower left arm/hand* 1-3: upper left arm; 4-6: abdomen

13-14: Upper right leg 1-2: abdomen; 3-4: upper left leg; 5-6: lower right leg

15: Lower right leg 1-3: upper right leg; 4-6: right foot

16: Right foot 1-6: lower right leg

17-18: Upper left leg 1-2: abdomen; 3-4: upper right leg; 5-6: lower left leg

19: Lower left leg 1-3: upper left leg; 4-6: left foot

20: Left foot 1-6: lower left leg

*For lower arm/hand roll a D6: on a 1-4 the forearm is hit, on a 5-6 the hand is hit.

Once we have determined location, we need to work out how seriously the character has been hurt. For this we refer to the wound table on the next page.

Attacks and the wounds they cause are divided into two categories: Lethal and non-lethal.

There are five kinds of lethal wound: Scratch (SC) Flesh Wound (FW), Crippling Wound (CW), Mortal Wound (MW) and Death/Amputation (DA); and four kinds of non-lethal wound: Stinging (ST), Bruised (BR), Stunned (ST) and Knocked Out (KO).

To determine what kind of wound a successful attack causes, roll D10, add or subtract the relevant modifiers, and find the result in the row corresponding to the attack's DC on the wound table.

Wound/damage roll modifiers:

Range:

At every fourth range band beyond Close (V Long and V Distant): -1 to Damage Class

Penetration vs. Armour:

PEN less than AV: Zero penetration

If DC > than AV, attack causes a non-lethal wound at DC minus AV

PEN equals AV: Low penetration

Attack penetrates with -4 modifier to wound roll

Pen greater than AV: Full penetration

Attack penetrates with no modifier to wound roll

Target Size: Wound Modifier:

1 +3

2 +2

3-4 +1

5-7 0

8-9 -1

10 -2

11-12 -3

13-14 -4

15-16 -5

17-18 -6

19-20 -7

21-22 -8

23-24 etc. -9 etc.

For melee attacks only:

Attacker Strength: DC:

1 -3

2 -2

3-4 -1

5-7 0

8-9 +1

10 +2

11-12 +3

13-14 +4

15-16 +5

17-18 +6

19-20 +7

21-22 +8

23-24 etc. +9 etc.

Location: Wound Modifier:

Upper limb: -2/-1 vs cutting weapons

Lower limb: -1/0 vs cutting weapons

Hand or foot: -1/+1 vs cutting weapons

Abdomen: +1

Chest: +2

Heart: +5

Face/neck: +2

Skull: +5

Previous wound state at location:

FW/BR: +1

CW/ST: +2

MW/KO: +3

		D10 Roll
		1	2	3	4	5	6	7	8	9	10
Damage Class	⅙	SC/SG	SC/SG	SC/SG	SC/SG	SC/SG	FW/BR	FW/BR	FW/BR	FW/BR	CW/ST
	⅓	SC/SG	SC/SG	SC/SG	SC/SG	FW/BR	FW/BR	FW/BR	FW/BR	CW/ST	CW/ST
	½	SC/SG	SC/SG	SC/SG	FW/BR	FW/BR	FW/BR	FW/BR	CW/ST	CW/ST	CW/ST
	1	SC/SG	SC/SG	FW/BR	FW/BR	FW/BR	FW/BR	CW/ST	CW/ST	CW/ST	CW/ST
	2	SC/SG	FW/BR	FW/BR	FW/BR	FW/BR	CW/ST	CW/ST	CW/ST	CW/ST	MW/KO
	3	FW/BR	FW/BR	FW/BR	FW/BR	CW/ST	CW/ST	CW/ST	CW/ST	MW/KO	MW/KO
	4	FW/BR	FW/BR	FW/BR	CW/ST	CW/ST	CW/ST	CW/ST	MW/KO	MW/KO	MW/KO
	5	FW/BR	FW/BR	CW/ST	CW/ST	CW/ST	CW/ST	MW/KO	MW/KO	MW/KO	MW/KO
	6	FW/BR	CW/ST	CW/ST	CW/ST	CW/ST	MW/KO	MW/KO	MW/KO	MW/KO	DA/CW
	7	CW/ST	CW/ST	CW/ST	CW/ST	MW/KO	MW/KO	MW/KO	MW/KO	DA/CW	DA/CW
	8	CW/ST	CW/ST	CW/ST	MW/KO	MW/KO	MW/KO	MW/KO	DA/CW	DA/CW	DA/CW
	9	CW/ST	CW/ST	MW/KO	MW/KO	MW/KO	MW/KO	DA/CW	DA/CW	DA/CW	DA/CW
	10	CW/ST	MW/KO	MW/KO	MW/KO	MW/KO	DA/CW	DA/CW	DA/CW	DA/CW	DA/MW
	11	MW/KO	MW/KO	MW/KO	MW/KO	DA/CW	DA/CW	DA/CW	DA/CW	DA/MW	DA/MW
	12	MW/KO	MW/KO	MW/KO	DA/CW	DA/CW	DA/CW	DA/CW	DA/MW	DA/MW	DA/MW
	13	MW/KO	MW/KO	DA/CW	DA/CW	DA/CW	DA/CW	DA/MW	DA/MW	DA/MW	DA/MW
	14	MW/KO	DA/CW	DA/CW	DA/CW	DA/CW	DA/MW	DA/MW	DA/MW	DA/MW	DA/DA
	15	DA/CW	DA/CW	DA/CW	DA/CW	DA/MW	DA/MW	DA/MW	DA/MW	DA/DA	DA/DA
	16	DA/CW	DA/CW	DA/CW	DA/MW	DA/MW	DA/MW	DA/MW	DA/DA	DA/DA	DA/DA
	17	DA/CW	DA/CW	DA/MW	DA/MW	DA/MW	DA/MW	DA/DA	DA/DA	DA/DA	DA/DA
	18	DA/CW	DA/MW	DA/MW	DA/MW	DA/MW	DA/DA	DA/DA	DA/DA	DA/DA	DA/DA
	19	DA/MW	DA/MW	DA/MW	DA/MW	DA/DA	DA/DA	DA/DA	DA/DA	DA/DA	DA/DA
	20	DA/MW	DA/MW	DA/MW	DA/DA	DA/DA	DA/DA	DA/DA	DA/DA	DA/DA	DA/DA

How to use the wound table

First, total up all the positive and negative wound modifiers (for location, target Size, ammunition type and so on) Find the the attack's DC in the left-hand column. Roll D10 and count across the horizontal row for the DC to the corresponding box.

Next, apply the wound modifier: for positive modifiers (+1, +2 etc.) shift the result one column to the right. If you reach the right-hand edge of the table with point to spare, start moving down the rows instead. For negative modifiers (-1, -2 etc.), shift the result one column to the left. If you reach the left-hand edge of the table with points to spare, start moving up the rows.

Wound state definitions and effects

Lethal wounds:

Scratch (SC)

A Scratch bleeds and hurts a little (although the character may not even notice in the heat of battle). This does affect the character physically in any appreciable way, but they still have to make a Nerve check for being hit.

Flesh Wound (FW): A Flesh Wound is more than just a superficial scratch, but it is neither life-threatening nor greatly debilitating. It will bleed enough to leave drops and smears of blood on the ground and in other places, which other characters and some animals (sharks for instance) can track.

A character suffering a Flesh Wound must make a D10 roll equal to or less than their Nerve with a -3 die modifier, or pass out from pain and shock (effectively stunned: see non-lethal damage below).

Actions with the wounded location are made at a cumulative -1 modifier to the relevant character statistic for every flesh wound suffered.

Some examples of wound effects are as follows:

Arm or hand: -1 to Dexterity, Strength and Tech skills per FW for tasks to that arm.

Leg or foot: -1 to Agility and Strength skills per FW to that leg.

Face/Neck: -1 to Intelligence, Appearance and Empathy-based skills per FW.

Skull: -1 to Intelligence, Appearance and Empathy-based skills per FW, plus a 25 per cent chance that blood will flow down into the eyes, partially blinding the character.

Flesh wounds take one week to heal with an easy Medicine or average First Aid check.

Crippling Wound (CW): A Crippling Wound indicates a broken bone or severely lacerated major muscle, which renders the location useless until healed. A Crippling Wound is not life-threatening, but the character must roll equal to or under their Nerve with no modifier, or pass out (as with a Flesh Wound). It may bleed a lot and leave an easy-to-follow trail of blood.

Arm or hand: The character drops anything held in that hand and cannot pick up or manipulate anything.

Leg or foot: The character cannot walk and must make a Difficult Athletics roll to remain standing. They can move by hopping (⅓ walking speed) or using crutches (½ walking speed), furniture or scenery for support (⅓ walking speed), or by crawling (⅕ walking speed). The character can also climb at a -3 task modifier. If both legs are affected at once the character automatically collapses, unless already seated or lying.

Abdomen: The character cannot run and can only walk at ⅓ normal speed.

Chest: The same effects as a CW to the abdomen, plus the character suffers a -3 modifier per CW to all tasks due to shortness of breath and accompanying dizziness.

Face/Neck: The character cannot speak and has difficulty breathing, giving a

Skull: The wound renders the character unconscious (most likely with a skull fracture) until they have recovered to FW status.

Mortal Wound (MW): A major blood vessel or vital organ (such as a lung or the trachea) has been severed or badly damaged, and the character is bleeding or suffocating to death.

The wounded character must make an immediate Nerve -3 roll to remain conscious, and must then roll under their Constitution/Toughness every round to stay alive, with a cumulative +1 modifier to the roll every round after the first. They must keep rolling until they die or until the wound is stabilised. A natural roll of a one indicates that the wound has staunched by itself and the character is out of immediate danger. A Mortal Wound can be stabilised by another character on a successful Difficult Medicine or Very Difficult First Aid task, but if the character has more than one mortal wound, each must be treated separately.

Death/Amputation (DA): This is a wound which instantly kills the character beyond any hope of being saved through medical treatment, or which amputates a limb. Effects by location are as follows:

Skull: Shattering/fragmentation of the skull or other massive wound, with most brain tissue lost, or severing of spinal cord.

Face/Neck: Partial or complete severing of neck (decapitation).

Chest: Massive gaping chest wound.

Heart: Heart completely destroyed.

Abdomen: Disembowelment/evisceration. Treat as a Mortal Wound, but requiring a Very Difficult Surgery task or Nearly Impossible First Aid task to stabilise.

Upper Arm/Leg: Amputation above the elbow or knee. Treat as a Mortal Wound, but needing a Very Difficult Surgery task or Nearly Impossible First Aid task to stabilise.

Lower Arm/Leg: Amputation below the elbow or knee. Treat as a Mortal Wound.

Hand/Foot: Partial or full amputation below the wrist or ankle. Treat as a Mortal Wound but only needing an Average Surgery task or Difficult First Aid task to stabilise.

Non-lethal wounds:

For non-lethal attacks, hits to the heart location should be counted as chest hits.

Stinging (SG)

The blow stings or twinges, but does not even leave a bruise. The character suffers no debilitating effects.

Bruised (BR): The character has a nice shiny bruise where they were hit. Actions involving the affected location are at -1 per BR wound state for five minutes.

Stunned (ST): The location is temporarily incapacitated for 1D3 Rounds, after which the wound state is reduced to Bruised for five minutes. If the skull or face/neck is hit, the character is semi-conscious and cannot act (they just stagger around or fall over). If an arm or hand is hit, they drop anything held immediately, including ropes or ladders which you are hanging on to. If a leg or foot is hit, they cannot walk on it and must make an Average Athletics roll to stay on your feet. If both legs are affected at once they automatically collapse, unless already seated or lying. A ST wound state to the chest or abdomen leaves you winded – you cannot run and you can only walk at ⅓ normal speed.

Knocked Out (KO): You are knocked unconscious or crippled by the pain of the blow for 2D6+6 rounds, after which the wound state is reduced to Bruised for five minutes. If the skull or face/neck is hit, you are knocked unconscious. For the chest and abdomen, you are conscious but incapacitated and unable to stand. A limb is rendered useless, and in the case of a leg or foot the character must make a Difficult Athletics roll to remain standing.

A DA result from a non-lethal attack means that bone has been broken, counting as a Crippling Wound (CW) result from the lethal attack section. If the minimum roll for a DA result is exceeded by five points or more, the result is a Mortal Wound (MW) Thus, a short-range shotgun blast to a head could be lethal even if the victim was wearing a helmet that stopped the shot from penetrating. If the minimum roll for a DA result is exceeded by ten points, the result is a Death/Amputation (DA) wound. This reflects massive crushing damage or blast injuries from explosions.

Quick and Simple Wound Resolution

The rules for calculating wounds given above are detailed but complicated. They are probably too time-consuming to use in a fight between more than a handful of people. Furthermore, it doesn't really matter whether a nameless, faceless goon who's only in the game for one fight gets a flesh wound in the arm or the leg. Arguably hit locations should only be used for Player Characters and important NPCs, or not at all.

With that in mind, here is a simplified version of the wounding rules.

First there are no hit locations, and so no location modifiers to the wound roll.

A character's AV is based on the armour or cover protecting their torso, or the AV of the best-protected body location if the torso is uncovered.

A D6 is rolled to see if the attack hits the character's armour or an unprotected location. The number needed for this 'saving throw' is based on how much of the character's body is armoured or behind cover, which is counted in 'blocks'. The torso is two blocks, the head one, the arms one and the legs two, for a total of six for the whole body.

Blocks Protected Saving Throw

1 6

2 5 or more

3 4 or more

4 3 or more

5 2 or more

6 Automatic

Thus a character wearing a bullet-proof vest and a helmet would use the AV of the vest, but only on a D6 roll of 4,5 or 6. Otherwise an unarmoured location has been hit.

Penetration is handled more or less as normal: If the attack's PEN is less than the target's AV, the attack fails to penetrate. If PEN and AV are equal, the attack penetrates but with a -5 modifier to the wound roll. If PEN Is greater than AV, the attack penetrates with no modifier to the wound roll. We don't need to bother about non-lethal hits from high-damage weapons that fail to penetrate.

Wounds are rolled for on the wound table above, but with no modifiers for location, as already mentioned, and no modifiers for previously-suffered wounds. However, the modifiers for the Size stat are still used, as does the Strength modifier to DC for melee and unarmed combat attacks. The simplified wound results are as follows:

Lethal Attacks:

Scratch (SC): no effect

Flesh Wound (FW): -1 to all stats until healed. The character must make a Nerve check for morale or take cover, flee or surrender (as the GM deems appropriate)

Crippling Wound (CW): all stats halved. If two CWs are suffered, divide stats by three, if three CWs divide by four etc. The character must make a Nerve check for morale at -3 or take cover, flee, surrender or pass out (as the GM deems appropriate).

Mortal Wound (MW): as CW, but the character must make a toughness check to avoid dying every round (+1 to the roll for every round after the first) until they are stabilised by successful a First Aid task, roll a 1 (the wound stabilises on its own) or they fail the roll and die. The character must also make a Nerve check for morale at -3 or take cover, flee, surrender or pass out (as the GM deems appropriate).

Death/Amputation (DA): the character is killed immediately.

Non-Lethal Attacks:

Stinging (SG): no effect

Bruised (BR): -1 to all stats for five minutes

Stunned (ST): the character cannot act for 1D3 rounds.

Knocked Out (KO): the character is unconscious and out of the fight.

Super-Simple Wounding Rule:

This rule is presented in case things are still to complicated, or in case anyone wants to run a skirmish battle game with these rules.

Scratch (SC) and Flesh Wound (FW) results have no effect.

Crippling Wound (CW), Mortal Wound (MW) and Death/Amputation (DA) results mean the character is 'down' and out of combat as a casualty – injured, dying or dead in each case.