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-   -   MVDS and Mass Combat, revisited (http://forums.sjgames.com/showthread.php?t=12314)

 copeab 01-22-2006 07:44 AM

MVDS and Mass Combat, revisited

Some of you may remember me, quite a while back, listing Troop Strength (TS) values for various ground vehicles that have been written up in G:WWII books. The main problem was that all the TS values were subjective. Yesterday, I think I may have come up with a reasonable objective system that allows one to derive the TS value of a ground vehicle by formula.

I decided to break the TS into three components: firepower, armor and mobility. I would have liked these to have been equal components, but as things turned out, the first two are weighted a bit more heavily in the formula. Here is how each component breaks down:

Firepower: Find the average damage of the main gun; if the gun has both an armor-piercing and high-explosive component, only use the AP portion of the damage. Divide this by ten. If the main gun is not in a fully rotating mount (eg, a Hetzer or StuG), divide that result by two. To this, add 1 for every LMG and 2 for every HMG the vehicle carries.

Armor: Divide the front turret DR by ten. If the main gun is not located in the turret, or the main gun is a MG, use the front body DR, divided by ten.

Mobility: Find the off-road speed in MPH. This is the mobility component.

Add the firepower, armor and mobility components, then divide by two. The result is the TS of the vehicle.

This seems to work reasonably well for tanks and tank destroyers. I have not tested it for SP artillery, and it probably doesn't work for them.

 Kale 01-22-2006 08:19 AM

Re: MVDS and Mass Combat, revisited

Interesting. It's good to have some sort of consistant system. Now what about aircraft? @:-)

 copeab 01-22-2006 08:31 AM

Re: MVDS and Mass Combat, revisited

Quote:
 Originally Posted by Kale Interesting. It's good to have some sort of consistant system. Now what about aircraft? @:-)
I haven't even tried aircraft yet. As best as I can tell, they exist only to attack ground forces in the Mass Combat rules ;)

Oh, I'll note that the TS values for AFVs were designed to, very roughly, correspond to the 25/40/60 values for light/medium/heavy tanks. My TS numbers come out a little higher on average, but that's probably okay.

 copeab 01-23-2006 03:30 AM

Re: MVDS and Mass Combat, revisited

Here are calculated TS values for several vehicle, from the core book, the American book, the German book and the British book.

One change to the formula: If a vehicle is only armed with machine guns, then instead of the sum of the firepower, armor and mobility components being divided by two to find the TS, the sum is divided by three.

SdKfz 251/1: 6
M-3A1 halftrack: 6
Humber Scout Car: 6
Daimler Scout Car: 7
SdKfz 250/1: 7
Jeep: 7 (!) [this is almost all from the very high OR speed]
Panzer Ib: 11
Universal Carrier: 13
Light Tank Mk VI: 15
SdKfz 222: 16
Valentine III: 21
Panzer IIc: 23
Panzer IVd: 28
M-3 Stuart: 31
Matilda II: 33
Churchill IV: 35
Panzer IIIj: 36
M-4 Sherman: 39
Panzer IVh: 40
Hetzer: 41
T-34A: 43
M-10 Wolverine: 44
M-4A3E8: 50
Tiger: 53
Panther G: 68
Tiger II: 74

 Michele 01-24-2006 04:08 AM

Re: MVDS and Mass Combat, revisited

Brandon,

this is interesting, but it would be really useful only if it integrated everything. At present it seems focused on tanks, with other combat vehicles already not sounding all that right. If I want to assess mass-combat values I would need to factor in infantry, artillery, etc.

 copeab 01-24-2006 04:57 AM

Re: MVDS and Mass Combat, revisited

Quote:
 Originally Posted by Michele Brandon, this is interesting, but it would be really useful only if it integrated everything. At present it seems focused on tanks, with other combat vehicles already not sounding all that right. If I want to assess mass-combat values I would need to factor in infantry, artillery, etc.
Infantry would use the normal rules for calculating TS value. OTOH, I don't think the mass combat rules takes into account MG teams, anti-tank teams, etc.

Edit: An anti-tank team would probably best be handled as artillery that can only neutralize an armor advantage (although some infantry AT weapons did have an HE capability). The basic +TL to a soldier's TS for a rifle should probably assume a bolt-action rifle. A soldier with a semi-automatic rifle might get a +1 to this. I'm not sure about what modifiers to make for soldiers with SMGs or assault rifles. For machine guns, perhaps +(TL*1.5) for an LMG, +(TL*2) for a MMG and +(TL*3) for a HMG. This would just be for the MG gunner; anyone else in the crew has their TS figured as above.

The SdKfz 251/1 and M-3A1 halftrack, under mass combat rules, would have +6 TS, which is what they get with my formula. The SdKfz 250/1 is only one point higher. The jeep is admittedly a bit off, but, like most unarmored vehicles, probably should have (a low) TS assigned rather than calculated. While the Universal Carrier is a bit high (+11 TS), it carries only about 1/3 the number of infantry as the American and German halftracks.

As for artillery, it's given a flat TS of 100 under mass combat rules. Since that's probably for a 105mm piece, it might be reasonable to assign a TS to artillery equal to it's bore. Mortars, being much shorter ranged than howitzers and cannons, would probably have a TS of half bore. I'm not sure what to do about rockets. I probably would not make a distinction between towed and SP artillery for mass combat -- that's more of a strategic distinction than tactical one. Anti-tank and infantry guns, which are normally fired directly, are a different situation, which I haven't my up my mind on yet.

BTW, for those wondering, the GURPS Mass Combat system can be found in Compendium II and Roleplayer #30.

 Rupert 01-24-2006 06:31 PM

Re: MVDS and Mass Combat, revisited

Quote:
 Originally Posted by copeab As for artillery, it's given a flat TS of 100 under mass combat rules. Since that's probably for a 105mm piece, it might be reasonable to assign a TS to artillery equal to it's bore. Mortars, being much shorter ranged than howitzers and cannons, would probably have a TS of half bore.
While this is true, mortars are also (in the WWII period) likely to respond faster to calls for fire than artillery, and their bombs are more effective for a given bore than an artillery shell.

Quote:
 I'm not sure what to do about rockets. I probably would not make a distinction between towed and SP artillery for mass combat -- that's more of a strategic distinction than tactical one. Anti-tank and infantry guns, which are normally fired directly, are a different situation, which I haven't my up my mind on yet.
How do they come out if calculated like vehicles with no speed?

 copeab 01-24-2006 08:32 PM

Re: MVDS and Mass Combat, revisited

Quote:
 Originally Posted by Rupert While this is true, mortars are also (in the WWII period) likely to respond faster to calls for fire than artillery, and their bombs are more effective for a given bore than an artillery shell.
True. Mortars can also, for short periods, be fired at a fairly high rate of fire.

Quote:
 How do they [AT guns] come out if calculated like vehicles with no speed?
Basically 1/20 the average AP damage of the gun, with maybe a point or two od defense from a gun shield. I'm not sure if they should suffer the same firepower reduction as fixed mount guns; I would probably say yes.

 Michele 01-25-2006 04:17 AM

Re: MVDS and Mass Combat, revisited

Quote:
 Originally Posted by copeab True. Mortars can also, for short periods, be fired at a fairly high rate of fire. Basically 1/20 the average AP damage of the gun, with maybe a point or two od defense from a gun shield. I'm not sure if they should suffer the same firepower reduction as fixed mount guns; I would probably say yes.
Yes, unless they have universal mounts, like many AA guns had. We have the MVDS writeups to use as a guide.
Then again, 0-speed "vehicles" that can be manhandled by a pair of crewmen are more mobile than 0-speed "vehicles" that can't be moved without a mover.

 copeab 01-25-2006 06:14 AM

Re: MVDS and Mass Combat, revisited

Quote:
 Originally Posted by Michele Yes, unless they have universal mounts, like many AA guns had. We have the MVDS writeups to use as a guide.
I was referring to AT guns. AA guns, of course, nearly always have full movement on their mounts.

Quote:
 Then again, 0-speed "vehicles" that can be manhandled by a pair of crewmen are more mobile than 0-speed "vehicles" that can't be moved without a mover.
Despite the faxt that the 12.8cm Pak 44 was far too heavy to be manhandled, it was capable of 360 degree traverse on it's mount. From a quick scan of a book covering 20th century artillery, 60 degree traverse seems common for AT guns. Of course, a 37mm AT gun could fairly easily be moved by the crew to cover a greater arc, while a 128mm AT gun couldn't.

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