Proposed CT New Combat System

[tbeard1999]

I've offered this combat system in a private forum, but it occurred to me that it might make a decent CT combat system as well.

EDIT: THIS SYSTEM HAS BEEN REPLACED BY THE MORE COMPREHENSIVE "COMBAT SYSTEM C" (http://www.travellerrpg.com/CotI/Discuss/showthread.php?t=17021 )

EDITS: Added/changed a few armor ratings. Found out that full medieval plate was 2-3mm of soft steel (about 1.5mm of RHA equivalent); added options for more nuanced armor penetration. See expanded shotgun ammo later in thread.

Sequence

1. Roll to hit on 2D. Multiple hits may be scored by automatic weapons. Base to hit roll is 8+. Use standard CT modifiers. SMGs and weapons firing bursts get +2. Shotguns are +2. For every 2 points above 8 the modified roll is, score an extra hit (maximum 4 hits).

2. For each hit, roll penetration (1d6+penetration). If the roll equals or exceeds the target's armor rating, the hit penetrates. On a natural "6" halve the target's armor rating (round down). (The single d6 is preferred because it allows multiple hits to be rolled at the same time, rather than sequentially). Do not use the group hits or double attack rules from CT. Rules for heavier automatic weapons to come.

Example: Biff fires a TL10 ACR at Jasper (in TL10 rigid armor) and scores 2 hits. For each hit, Biff roll 1D and adds the ACR's penetration of 8. Any roll that equals Jasper's armor rating (12) penetrates. Biff rolls a 2 and a 5 for a total of 10 and 13. The first shot is stopped by Jasper's armor, the second penetrates. Biff rolls 4D damage.

3. Roll damage for penetrating hits. Damage is given for small arms; for larger weapons, damage is a number of dice equal to penetration/2 (unless otherwise stated). Damage is allocated exactly like CT.

Note that this system can play very fast because you can roll all penetration rolls at the same time and all damage rolls together (after the first hit).

Here are sample weapons and armor:

Armor
TL3 Rigid - 3 (half plate armor)
TL3 Rigid - 4 (full Plate armor)
TL5 Rigid - 5 ("flak jacket")
TL7 Rigid - 6
TL8 Rigid - 8
TL9 Rigid - 10
TL10 Rigid - 12
TL11 Rigid - 14
TL12 Rigid - 16 (aka "Combat Armor")
TL13 Rigid - 18 (aka "Combat Armor")
TL14 Rigid - 20 (aka "Combat Armor" or "Battle Dress")
TL15 Rigid - 22 (aka "Combat Armor" or "Battle Dress")
Reflec - +12 vs lasers

TL3 Flex - 2 (aka chainmail or Mesh?)
TL6 Flex - 4
TL7 Flex - 5
TL8 Flex - 6 (aka "Cloth")
TL9 Flex - 8
TL10 Flex - 9
TL11 Flex - 10
TL12 Flex - 11
TL13 Flex - 12
TL14 Flex - 13
TL15 Flex - 14

Weapons (Pen/Dmg)
Hands -2/1D
Claws 1/1D
Teeth 0/2D
Horns 0/2D
Hooves 1/2D
Stinger 2/3D
Thrasher 3/2D
Club 0/2D
Dagger 1/2D
Blade 2/2D
Foil 4/1D
Cutlass 3/3D
Sword 3/2D
Broadsword 3/4D
Bayonet 1/3D
Spear 0/2D
Halberd 1/3D
Pike 2/3D
Cudgel 1/2D
Body Pistol -1/2D
Pistol 0/3D
Carbine 1/3D
SMG 0/3D
Shotgun -1/4D
TL5 7.5mm Rifle 3/3D
TL7 5.5mm Assault Rifle 2/3D
TL5 7.5mm Sniper Rifle 4/3D
TL9 8mm ACR 6/3D
TL10 9mm ACR 8/4D
TL11 9mm ACR 10/4D
TL12 4mm Gauss Rifle 12/4D
TL13 4mm Gauss Rifle 14/4D
TL14 Plasma Rifle 16/6D
TL15 Fusion Rifle 18/8D

TL9 Pistol 4/4D*
TL10 Pistol 5/4D*
TL11 Pistol 6/4D*
TL12 Pistol 7/4D*
TL13 Gauss Pistol 8/3D
TL14 Gauss Pistol 9/3D
TL15 Gauss Pistol 10/3D

*HEAP warhead.

The armor/penetration scale is posted later.

TL15 rigid armor (almost certainly powered) provides the equivalent of 8cm rolled homogenous armor protection. This makes a TL15 soldier about as well protected as many WWII era (TL5) main battle tanks (the T-34/76 had about 7.6 cm RHA protection across the front). This is consistent with reasonable projections of materials tech IMHO.

The TL12 Gauss Rifle will penetrate about 5cm RHA, making it actually useful against TL5-6 light tanks (4-5cm RHA armor).

Sample Vehicles
M1A2 SEP Abrams TL8 MBT:
Armor: 55 (58 vs HEAT)
Main Gun Penetration: 52 at 2000m; 26D damage (KE); no burst effect

A TL15 heavy tank should have the following ratings:
Armor: 77
Main Gun Penetration: 73 at 14km (36D damage); fusion gun burst effect (pen 46, 23D damage, -1 pen per m from impact point, -1D damage per 2m from impact point).

A TL6 light tank looks like this:
Armor: 15
3.5cm gun penetration: 18 at 2km (9D damage); HE burst effect (pen 3, 1D damage, -1 pen per 2m from impact point; -1D damage per 4m from impact)

More Nuanced Systems

In reality, no armor system will cover every area of the body with full protection. Due to weight and cost considerations, armor will tend to protect the most critical areas the best and scrimp on less critical areas. The base system seriously abstracts this by allowing a penetration roll of 6 to halve armor. For more detail, here are some optional rules:

Option 1: Armor coverage is partial (only covers most critical areas like head and chest), comprehensive (covers most areas, but gaps remain, or complete (self-explanatory). Partial armor is halved if the penetration roll is 4+. Comprehensive armor is halved if the penetration roll is 5+. Complete armor is halved if the penetration roll is 6+. Regardless of armor rating, any hit on "halved" armor will do at least 1D damage, as long as the firing weapon does at least 2D damage.

Option 2: If the penetration roll is a 6 (5 or 6 if the armor is partial/comprehensive), armor rating is reduced to 1/4 of its rating (round down).

Option 3: If you want highly skilled characters to be able to defeat armor (my mind is not made up on this), allow characters to aim for weak spots in the armor. Against complete armor, the roll is -4. Against comprehensive armor, it's -3. Against partial, it's -2. If a hit is scored, here are the options:

(a) The armor is halved. (If a 6 is then rolled for penetration, the armor is ignored). Regardless of the penetration roll, at least 1D damage is done.

(b) The armor is quartered (If a 6 is then rolled for penetration, the armor is ignored). Regardless of the penetration roll, at least 1D damage is done.

(c) The armor is ignored.

Pick the option for your campaign that best fits your conception of how body armor works.

Also, some folks would like to see more blunt force trauma on non-penetrating wounds. Frankly, I think that Hollywood has greatly overstated this effect, but here's a clean way to portray it:

If a hit does 3D+ damage, even a non-penetrating hit may stun the target. For *each* hit, the target must make a 2D roll of 8+ to avoid being stunned (substitute whatever task system you want), DM +2 if STR 9+, DM+1 for gauss weapons, DM-2 if shotgun at close or short range. If he misses any stun roll, he's -2 on his next physical action. He must also make a DEX roll to avoid being knocked down (5+; DM +2 if DEX 9+). At the referee's discretion (and depending on the JWR (John Woo Rating) in the campaign, he may be knocked back 1d6 meters). Knockback does not occur with lasers.


Also, see the posting below for better shotgun ammo.

Coming soon -- range information for weapons.

 

[tbeard1999]

Armor/Penetration Scale

Here's the entire scale:

	 RHA	 Armor
 Pen 	 (cm)	 Rating 
 -2	 0.01 	 2 
 -1	 0.06 	 3 
 -   	 0.13 	 4 
 1 	 0.25 	 5 
 2 	 0.50 	 6 
 3 	 0.75 	 7 
 4 	 1.00 	 8 
 5 	 1.50 	 9 
 6 	 2.00 	 10 
 7 	 2.50 	 11 
 8 	 3.00 	 12 
 9 	 3.50 	 13 
 10 	 4.00 	 14 
 11 	 4.50 	 15 
 12 	 5.00 	 16 
 13 	 5.50 	 17 
 14 	 6.00 	 18 
 15 	 6.50 	 19 
 16 	 7.00 	 20 
 17 	 7.50 	 21 
 18 	 8.00 	 22 
 19 	 8.50 	 23 
 20 	 9.00 	 24 
 21 	 9.50 	 25 
 22 	 10.00 	 26 
 23 	 10.50 	 27 
 24 	 11.00 	 28 
 25 	 11.50 	 29 
 26 	 12.00 	 30 
 27 	 12.50 	 31 
 28 	 13.00 	 32 
 29 	 13.50 	 33 
 30 	 14.10 	 34 
 31 	 15.40 	 35 
 32 	 16.80 	 36 
 33 	 18.30 	 37 
 34 	 20.00 	 38 
 35 	 21.80 	 39 
 36 	 23.80 	 40 
 37 	 25.90 	 41 
 38 	 28.30 	 42 
 39 	 30.80 	 43 
 40 	 33.60 	 44 
 41 	 36.70 	 45 
 42 	 40.00 	 46 
 43 	 43.60 	 47 
 44 	 47.60 	 48 
 45 	 51.90 	 49 
 46 	 56.60 	 50 
 47 	 61.70 	 51 
 48 	 67.30 	 52 
 49 	 73.40 	 53 
 50 	 80.00 	 54 
 51 	 87.20 	 55 
 52 	 95.10 	 56 
 53 	 104 	 57 
 54 	 113 	 58 
 55 	 123 	 59 
 56 	 135 	 60 
 57 	 147 	 61 
 58 	 160 	 62 
 59 	 174 	 63 
 60 	 190 	 64 
 61 	 207 	 65 
 62 	 226 	 66 
 63 	 247 	 67 
 64 	 269 	 68 
 65 	 293 	 69 
 66 	 320 	 70 
 67 	 349 	 71 
 68 	 381 	 72 
 69 	 415 	 73 
 70 	 453 	 74 
 71 	 494 	 75 
 72 	 538 	 76 
 73 	 587 	 77 
 74 	 640 	 78 
 75 	 698 	 79 
 76 	 761 	 80 
 77 	 830 	 81 
 78 	 905 	 82 
 79 	 987 	 83 
 80 	 1,080 	 84 
 81 	 1,170 	 85 
 82 	 1,280 	 86 
 83 	 1,400 	 87 
 84 	 1,520 	 88 
 85 	 1,660 	 89 
 86 	 1,810 	 90 
 87 	 1,970 	 91 
 88 	 2,150 	 92 
 89 	 2,350 	 93 
 90 	 2,560 	 94 
 91 	 2,790 	 95 
 92 	 3,040 	 96 
 93 	 3,320 	 97 
 94 	 3,620 	 98 
 95 	 3,950 	 99 
 96 	 4,310 	 100 
 97 	 4,700 	 101 
 98 	 5,120 	 102 
 99 	 5,580 	 103 
 100 	 6,090 	 104 
 101 	 6,640 	 105 
 102 	 7,240 	 106 
 103 	 7,900 	 107 
 104 	 8,610 	 108 
 105 	 9,360 	 109 
 106 	 10,200 	 110 
 107 	 11,200 	 111 
 108 	 12,200 	 112 
 109 	 13,300 	 113 
 110 	 14,500 	 114 
 111 	 15,800 	 115 
 112 	 17,200 	 116 
 113 	 18,800 	 117 
 114 	 20,500 	 118 
 115 	 22,300 	 119 
 116 	 24,400 	 120 
 117 	 26,600 	 121 
 118 	 29,000 	 122 
 119 	 31,600 	 123 
 120 	 34,400 	 124

So a tank with 10 cm RHA (rolled homogeneous steel armor) will have an armor value of 26. If its main gun penetrates 10 cm RHA at 2000 meters, its penetration is 22 and it does 11D damage.

 

[tbeard1999]

Customization Options--Rifles

Here are some customization options for weapons. Unless noted, no other variables change (if cost isn't expressly addressed, the ammo costs the same, for instance):

For Rifles and ACRs:
--Carbines will have a shorter effective range.
--Carbines may have -1 to penetration and/or -1D damage (less powerful bullet; different ammo than rifle)
--Sniper versions will have a longer effective range.
--Slug ammo will be cheaper, and have 1/2 the penetration (round up)
--HE ammo will do +2D damage, but penetration is 1/3 (round down)
--Ammo may be made at a higher tech level. DS ammo or slug ammo penetration is increased by 1 per 2 tech levels, maximum bonus of +2. At referee's discretion, the weapon may fail catastrophically, or wear out much faster.
--Integral grenade launchers may be added
--Integral electronic sights may be added
--Weapons may be built at higher TL. For instance, you can build a TL9 ACR at TL10. The weapon will be cheaper and will be very reliable (it's a mature tech). It can fire higher TL ammo without catastrophic failures, or higher wear and tear.

More to come.

 

[mike wightman]

Too complicated for my tastes but a nicely thought out system.

I like the armour scale.

I only have 2 rolls in combat in my house rules - roll to hit and roll for damage with armour subtracting damage dice in a hybrid T20/T4 manner.

Oh, and a while ago I raised the basic roll to hit with a gun in a firefight to 12+, with hefty DMS for remaining still and aimed firing - matches real world combat statistics better this way. The other way is keep the 8+ target but impose negative DMs for firing while moving and snap shots.

 

[jimg]

At first glance, I like the system quite a bit.

One question:

1. Roll to hit on 2D. Multiple hits may be scored by automatic weapons. Base to hit roll is 8+. Use standard CT modifiers. SMGs and weapons firing bursts get +2. Shotguns are +2. For every 2 points above 8 the modified roll is, score an extra hit (maximum 4 hits).

...

Shotgun -1/4D

Maybe I'm misreading this, but it looks like you are saying that a shotgun can provide multiple hits. Would each hit be 4d6? This seems a bit excessive.

EDIT: my mistake, after rereading it, I see you say that "Multiple hits may be scored by automatic weapons" The phrasing of the paragraph threw me.

 

[tbeard1999]

At first glance, I like the system quite a bit.

One question:



Maybe I'm misreading this, but it looks like you are saying that a shotgun can provide multiple hits. Would each hit be 4d6? This seems a bit excessive.

EDIT: my mistake, after rereading it, I see you say that "Multiple hits may be scored by automatic weapons" The phrasing of the paragraph threw me.

Correct. I should probably make it clearer, but this was a first draft sketch.

 

[tbeard1999]

Too complicated for my tastes but a nicely thought out system.

Since I am extremely intolerant of complex and fussy mechanics, I'd really like to know which elements seemed complicated to you. I designed it to be a fast-playing alternative to other systems that try to separate damage and penetration, so I've failed if it isn't fast playing.

 

[mike wightman]

Three rolls instead of two - that simple really

I roll to hit and roll for damage - penetration/armour/damage are dealt with by the armour subtracting damage dice T4/T20 style and various weapons ammo types being better or worse at reducing armour.

 

[dean]

Three rolls instead of two - that simple really

I roll to hit and roll for damage - penetration/armour/damage are dealt with by the armour subtracting damage dice T4/T20 style and various weapons ammo types being better or worse at reducing armour.

Three rolls doesn't make it more complex, just ever so slightly more time consuming.
And, if armor is not penetrated, no damage is rolled anyway (just as no damage is rolled if hits don't occur in a two-roll system).

I do agree with your prior post about making a non-aimed, moving, dodging shot a bas "12" roll. Hits should be debilitating, if not lethal, but not all that incredibly common.

 

[mike wightman]

Over the years I must have tried every possible Traveller combat system ever devised.

Roll to hit, roll location, roll penetration (based on Striker), roll damage was the most complicated.

There is actually no need for more than one roll, butmy plyers over the years have never been happy with that model

Roll to hit, roll damage - take away some dice or damage due to armour mitigation - very simple.

Working out the damage dice, the armour values, the effect of armour piercing ammo etc. very complicated, but in play 2 rolls trumps 3 in my gaming group's opinion.

 

[tbeard1999]

Three rolls instead of two - that simple really

I roll to hit and roll for damage - penetration/armour/damage are dealt with by the armour subtracting damage dice T4/T20 style and various weapons ammo types being better or worse at reducing armour.

Yeah, I've come around to like the T4 damage/armor mechanic. It's among the cleanest ways I've seen to separate damage and penetration (vie the limit of 3D damage for most weapons). However, there are two problems with the system (and YMMV on how serious they are):

1. You have to tell your players the armor value of what they're shooting at, or you have to roll their damage yourself. Don't care for either option.

2. Damage tends to become far less dramatic. In my campaign, which uses the T4 damage mechanic, players wind up getting worn down by many hits, each of which do 1 or 2 dice damage.

The system I posted addresses both concerns -- though candidly, it was proposed in the private forum *after* the T4 system was rejected. And after playing around with it today, I'm starting to really like it.

Regarding the 3 die rolls, consider this -- the total amount of time spent resolving a hit may well be equal to or less than a mechanic with two rolls, since each roll is relatively simple and multiple hits can be parallel processed. Thanks for the comments.

 

[Icosahedron]

I've only glanced at your mechanics, and I certainly haven't playtested them, but my objection would be that AIUI, you have re-invented all the armour values and they are no longer compliant with any version of Traveller, so devices/vehicles generated with Striker or FFS would need to be converted to your system - and there is no obvious conversion formula. Is my understanding correct?

 

[tbeard1999]

I've only glanced at your mechanics, and I certainly haven't playtested them, but my objection would be that AIUI, you have re-invented all the armour values and they are no longer compliant with any version of Traveller, so devices/vehicles generated with Striker or FFS would need to be converted to your system - and there is no obvious conversion formula. Is my understanding correct?

Actually, no, although it's my fault for not pointing it out. I designed it for compatibility with Striker, MT and FFS so that I can take advantage of my own library of designs.

Also, this system is compatible with any design sequence that outputs real world armor and penetration levels. Just figure out how many cms of steel, then use the chart. This makes it compatible with either version of FFS, GURPS Vehicles, Guns Guns Guns, etc.

Striker and MegaTraveller use a semi-logarithmic armor/pen scale. Here's a conversion chart:

------New System-----
RHA		Armor	Striker/MT
(cm)	Pen	Value	AV
-   	-2	2	0
0.01	-1	3	0
0.13	 0   	4	0
0.25	1	5	1
0.5	2	6	2
0.75	3	7	3
1	4	8	4
1.5	5	9	6
2	6	10	8
2.5	7	11	10
3	8	12	12
3.5	9	13	14
4	10	14	15
4.5	11	15	16
5	12	16	18
5.5	13	17	19
6	14	18	20
6.5	15	19	21
7	16	20	22
7.5	17	21	22
8	18	22	23
8.5	19	23	24
9	20	24	24
9.5	21	25	25
10	22	26	26
10.5	23	27	26
11	24	28	27
11.5	25	29	27
12	26	30	28
12.5	27	31	28
13	28	32	29
13.5	29	33	29
14.1	30	34	30
15.4	31	35	31
    	+1	+1	+1

 

[Deathstalker]

Not to try and be harsh, (especially on one of my first posts) but I got a link to this from someone else, and this was my response (with a few edits), based on a mostly TL10-12 system:

Interesting system. Read through it once, I'm not sure how much I like it, and also, I think that it's intended for a more nifty weapon setting than we have. Reading it again...

Looking at it now, I'm comparing, using anything but special weapons (ACR, HEAP shooting pistols, gauss pistols, etc.), the TL10 'flex' armor value of 9 (Not sure I get what that's supposed to be, Mesh?) will stop
any of the standard weapons cold. As they have no/little penetration.

In fact, only on a 6 on the penetration roll do they even hurt.

In fact the only TL10 or below, as that's about where most of our stuff is, and provides a nice benchmark, weapons that can do damage on anything below a 6, are a sniper rifle (5+), ACR (3+/1+, TL 9/10), and
the TL9/10 pistols with HEAP ammo (5+/4+). From a look at TL12, it looks similar, and in fact the Shotgun, won't even penetrate, -1+6 = 5 vs 11/2 = 5. Hrm it gets worse, at TL13, because at TL13, even a 12/2
(flex) on a 6 on the penetration roll doesn't penetrate, for most weapons.

If you assume skill-1, then on a purely average (7) to hit roll, they hit, but only 1/6 times do they do any damage firing at someone with conventional weapons. That's for the flex armor (listed as Mesh). Not
even the rigid armor (I'd presume like cloth, and later combat armor/battle dress). That's probably a bit low.

So not usable as written, for personal combat, IMO. There is too much range in weapon penetration, and too much bias towards high tech weapons/armor. Might be worth doing if there are ever vehicle combats
though.

(Frankly, if someone shoots you with a tommy gun, (TL 4?) repeatedly, you *will* go down, because either your armor will fail, or they will hit your head or another unprotected part. Same for a pistol. Unless the face is covered by armor, which CT wise, I don't believe it is unless it's a Vacc suit, Combat Armor, Battledress and maybe a Combat Environment Suit (I can't recall if that's with a helmet or not.))

Maybe if the armor were something like a 2 for naked, 3 for jack/mesh, 4 for cloth and 5 for combat armor, (possibly +1 on the last two, maybe a bit higher on battledress.) and the weapon mod was a lot narrower, say -2 to +2 at most for any conventional small arms. Plasmas & Gauss might be higher (I'd say maybe a +3), but still, not quite as bad.

If it goes for 6 or 7 on battledress, only a lucky hit from most weapons (Hit + nat 6 on penetration) will actually hurt the wearer, and even Plasma/Gauss (+3) will only have a 50% or 33% chance to damage (and very likely kill) someone in battledress. (And frankly, it's battledress, it should be able to sometimes take a really nasty shot and survive. (Might be GM induced penalties, like being blinded as all the cameras got crispified, weapons, etc))

 

[tbeard1999]

Not to try and be harsh, (especially on one of my first posts) but I got a link to this from someone else, and this was my response (with a few edits), based on a mostly TL10-12 system:

Interesting system. Read through it once, I'm not sure how much I like it, and also, I think that it's intended for a more nifty weapon setting than we have. Reading it again...

Looking at it now, I'm comparing, using anything but special weapons (ACR, HEAP shooting pistols, gauss pistols, etc.), the TL10 'flex' armor value of 9 (Not sure I get what that's supposed to be, Mesh?) will stop
any of the standard weapons cold. As they have no/little penetration.

In fact, only on a 6 on the penetration roll do they even hurt.

Unfortunately, this is a very realistic condition:

1. Pistols, by their very nature, are low penetration weapons. Even now, at TL8, relatively light body armor will stop all pistol bullets (including even the mighty .44 magnum). The same is true of shotguns.

2. The only way to increase penetration will be to dramatically increase velocity or change the warheads. With pistols, increasing velocity is not really much of an optiondue to short barrel length. HEAP warheads are far more likely IMHO, and you'll note that this is exactly what I propose will happen.

In fact the only TL10 or below, as that's about where most of our stuff is, and provides a nice benchmark, weapons that can do damage on anything below a 6, are a sniper rifle (5+), ACR (3+/1+, TL 9/10), and
the TL9/10 pistols with HEAP ammo (5+/4+). From a look at TL12, it looks similar, and in fact the Shotgun, won't even penetrate, -1+6 = 5 vs 11/2 = 5. Hrm it gets worse, at TL13, because at TL13, even a 12/2
(flex) on a 6 on the penetration roll doesn't penetrate, for most weapons.

Again, pretty realistic. The lesson is that low tech weapons do not fare well against high tech armor. As noted above, we're already seeing this with TL8 body armor.

Now, one thing that the system abstracts is the fact that body armor cannot cover the entire exposed area of the body with full armor protection. A rigid armor system that mostly does that would weigh 50+ lbs (about like a suit of medieval plate armor). And even there, some areas are exposed (inside of arms, back of calves, etc.). So no matter how tough the armor, there's a chance of getting wounded (usually in a non-critical location).

This is the reason for halving the penetration if the penetration roll is 6+. The only other way to do it is to introduce hit locations, which I'm desperate to avoid.

A more nuanced system, which I've been playing around with is at the end of the post.

If you assume skill-1, then on a purely average (7) to hit roll, they hit, but only 1/6 times do they do any damage firing at someone with conventional weapons. That's for the flex armor (listed as Mesh). Not
even the rigid armor (I'd presume like cloth, and later combat armor/battle dress). That's probably a bit low.

Well, again, you're matching modern armor with relatively ancient weapons. I'm pretty comfortable with the idea that armor will overmatch far older weaponry. You can clearly see this dynamic at work with armored fighting vehicles. A late WW2 (TL6) Jagdtiger averaged 21cm of steel armor across its front and its gun could penetrate about 16cm of steel armor at 2000m. A TL M1A2 SEP Abrams, about the same size, has 83cm of front armor and a gun that can penetrate about 88cm of armor at 2000m. The rounds from the Jagdtiger will simply bounce off the M1A2.

BTW, "flex" armor is armor that does not incorporate rigid plates for ballistic protection. At TL8, such armor is only effective against pistol, shotgun and fragmentation rounds. To deal with rifles, the armor has to incorporate rigid plates (usually ceramic or polyethelene). At each tech level, the flex armor is really only effective against pistols, shotguns and fragmentation rounds.

"Cloth" armor in CT is "flex" armor. And in CT, its effectiveness is dramatically overstated against rifles.

So not usable as written, for personal combat, IMO. There is too much range in weapon penetration, and too much bias towards high tech weapons/armor. Might be worth doing if there are ever vehicle combats though.

No question that the system is different from CT. It is, after all, a different system. However, I do think that it is a far more reasonable portrayal of future weaponry.

(Frankly, if someone shoots you with a tommy gun, (TL 4?) repeatedly, you *will* go down, because either your armor will fail, or they will hit your head or another unprotected part.

At TL8, armor failure is an issue because of the use of ceramics (which are super hard, but prone to shatter on impact). A great deal of effort is going into resolving this problem, and success is being seen--the latest standards for body armor require resistance against multiple impacts. Backing materials (which also reduce blunt trauma) and suspensions (i.e., epoxy) seem to be common solutions. I chose to assume that this problem would be largely resolved.

Interestingly, you can now get face shields that are proof against all pistol bullets. I've assumed that in my system.

But there's no question that body armor will never protect 100% of the body at full strength. Therefore, some kind of mechanic is needed to handle hits on weaker points.

More Nuanced Systems

Option 1: Armor coverage is partial (only covers most critical areas like head and chest), comprehensive (covers most areas, but gaps remain, or complete (self-explanatory). Partial armor is halved if the penetration roll is 4+. Comprehensive armor is halved if the penetration roll is 5+. Complete armor is halved if the penetration roll is 6+. Regardless of armor rating, any hit on "halved" armor will do at least 1D damage, as long as the firing weapon does at least 2D damage.

Option 2: If the penetration roll is a 6 (5 or 6 if the armor is partial/comprehensive), armor rating is reduced to 1/4 of its rating (round down).

Option 3: If you want highly skilled characters to be able to defeat armor (my mind is not made up on this), allow characters to aim for weak spots in the armor. Against complete armor, the roll is -4. Against comprehensive armor, it's -3. Against partial, it's -2. If a hit is scored, here are the options:

(a) The armor is halved. (If a 6 is then rolled for penetration, the armor is ignored). Regardless of the penetration roll, at least 1D damage is done.

(b) The armor is quartered (If a 6 is then rolled for penetration, the armor is ignored). Regardless of the penetration roll, at least 1D damage is done.

(c) The armor is ignored.

Pick the option for your campaign that best fits your conception of how body armor works.


BTW, Rigid armor weighs ~50 lbs if comprehensive, ~25 lbs if comprehensive; ~15 lbs if partial. Flex armor weighs ~30 lbs if comprehensive, ~20 lbs if comprehensive, ~12 lbs if partial. Helmets (proof against pistols) weigh 3lbs; faceshields (proof against pistols) weigh 2.5 lbs.

 

[tbeard1999]

We Should Have Shotguns...

As a referee and a player, I really like shotguns. However, any reasonably accurate armor system will weaken shotguns severely. So here are some thoughts on how to make shotguns still relevant.

1. A shotgun is a large calibre (18.5mm /12 gauge), smoothbore weapon that can generate reasonably high pressures. This makes it a potentially very versatile weapon. At higher TLs, a variety of high tech ammo becomes available. Shotguns may fire advanced shotgun ammo of up to 2 tech levels higher. TL5-early8 shotguns may malfunction with this ammo (a roll of 2 is jammed weapon). TL9+ shotguns are built with specialized ammo in mind (and can be customized at TL5+) and will not jam.

2. APFSDS rounds. At late TL8, armor piercing, fin-stabilized discarding sabot rounds become available for shotguns that make them a premier armor-killed (if short ranged). At Tl 9-10, the 7mm penetrators are made from depleted uranium or tungsten with a plastic sabot. When firing APFSDS rounds, shotguns fire semiautomatically and lose their normal to hit bonus. However, range is significantly improved. These are military rounds, so availablility may be unduly restricted.

TL	Pen/Dmg
8	5/3D
9	7/3D
10	9/3D
11	11/3D
12	13/3D
13	15/3D
14	17/3D
15	19/3D

3. HEAP rounds. At TL9, high explosive armor piercing rounds become available for shotguns. They are less effective at armor piercing than APFSDS, but they do a tremendous amount of damage. When firing HEAP rounds, shotguns fire semiautomatically and lose their normal to hit bonus. Heap rounds also have a fragmentation effect and will attack anything within a 1m radius with. Pen is halved (maximum 4) and damage is 1D. TL5-8 shotguns firing HEAP ammo will not jam (velocity is not any higher). These are military rounds, so availablility may be unduly restricted (although they may be common on less settled worlds with Really Big Critters). A variant of this ammo (which would be far more likely to be avaialble in the civilian market) eliminates the fragmentation effect, but otherwise acts and costs the same (called HEAT-S).

TL	Pen/Dmg
9	5/5D
10	7/5D
11	10/5D
12	12/5D
13	14/5D
14	16/5D
15	18/5D

4. Flechette rounds. At TL9, flechette rounds become available for shotguns. The +2 to hit bonus for shotguns is increased to +3 when firing flechettes. Range is dramatically improved as well. These are military rounds, so availablility may be unduly restricted.

TL	Pen/Dmg	Hit Bonus
9	4/3D
10	5/3D
11	6/3D
12	7/4D
13	8/4D
14	9/4D
15	10/4D

5. High powered ammo. Like other CPR weapons of TL9-12, shotguns benefit from far better propellants and exotic, dense bullet materials like depleted uranium, tungsten, crystaliron, etc. Normal shotgun, if built to TL9+ specs, will perform better than their TL5 equivalents. These are not military rounds, so availablility shouldn't be unduly restricted.

TL	Pen/Dmg	Hit Bonus
9	3/4D
10	4/4D
11	5/4D
12	6/4D
13	7/4D

6. Slugs. This is a big slug. The shotgun loses its to hit bonus, but damage and penetration are improved. At higher tech levels, better propellants and materials improve performance seriously. These are not military rounds, so availablility shouldn't be unduly restricted.

TL	Pen/Dmg	Hit Bonus
5-8	3/6D
9	4/6D
10	5/6D
11	6/6D
12	7/6D
13	8/6D

 

[tbeard1999]

Armor and Law Levels

For referees concerned that low tech weapons may be made obsolete, consider that body armor (especially rigid body armor) is likely to be controlled just like firearms. I suggest that you throw law level or less for rigid body armor to be made illegal. If so, then throw law level or less for flex armor to also be illegal. Of course, partial flex can be tailored to be relatively inconspicuous (cost x2 at least). But partial flex is far less help against rifles. And it's still (maybe) illegal.

And if there's no body armor, even primitive muskets will mess you up.

 

[pendragonman]

And if there's no body armor, even primitive muskets will mess you up.

~55 to 60 caliber will do that.

 

[tbeard1999]

Superceded

EDIT: THIS SYSTEM HAS BEEN REPLACED BY THE MORE COMPREHENSIVE "COMBAT SYSTEM C" (http://www.travellerrpg.com/CotI/Discuss/showthread.php?t=17021 )

 

[Icosahedron]

Actually, no, although it's my fault for not pointing it out. I designed it for compatibility with Striker, MT and FFS so that I can take advantage of my own library of designs.

Also, this system is compatible with any design sequence that outputs real world armor and penetration levels. Just figure out how many cms of steel, then use the chart. This makes it compatible with either version of FFS, GURPS Vehicles, Guns Guns Guns, etc.

Striker and MegaTraveller use a semi-logarithmic armor/pen scale. Here's a conversion chart:

------New System-----
RHA		Armor	Striker/MT
(cm)	Pen	Value	AV
-   	-2	2	0
0.01	-1	3	0
0.13	 0   	4	0
0.25	1	5	1
0.5	2	6	2
0.75	3	7	3
1	4	8	4
1.5	5	9	6
2	6	10	8
2.5	7	11	10
3	8	12	12
3.5	9	13	14
4	10	14	15
4.5	11	15	16
5	12	16	18
5.5	13	17	19
6	14	18	20
6.5	15	19	21
7	16	20	22
7.5	17	21	22
8	18	22	23
8.5	19	23	24
9	20	24	24
9.5	21	25	25
10	22	26	26
10.5	23	27	26
11	24	28	27
11.5	25	29	27
12	26	30	28
12.5	27	31	28
13	28	32	29
13.5	29	33	29
14.1	30	34	30
15.4	31	35	31
    	+1	+1	+1

Ah, I missed that, thanks for the clarification.

Another nitpick, if I may...
Your AV and the Striker/MT AV agree at 24,25,26, and then diverge again. Personally, I'd be inclined to have them agree at 24+, so that at 31+ all three columns agree. Unless I've missed some subtle reason why not? EDIT: In fact the AV columns are close enough after 12 that I wouldn't bother with the difference...

I've not opened the System C pdf yet, I'll take a look later.