Topic: Spacemaster Vehicle Weapon Marks vs Real World equivalents

[ravenstorm]

Hi, so I have just joined today..although ive been playing rolemaster and spacemasters for years, in its many different forms...and I have a question as Ive looked around for ages and can't find any help 

While I like the idea of vehicle weapon mark numbers, does anybody know of any resources or a way of trying to establish what a real world equivalent would be...for example is a mark 6 autocannon the equivalent of say a 25mm autocannon...

I know in spacemaster, personal firearms are already done..what with firearms having their caliber listed as well as their mark number...

I would be grateful for any help on this...

Thanks

[markc]

  Unfortunately no there is no way to do that. You might be able to make inferences by looking at TL levels and the TL levels the weapons were introduced. But even that is going to require a lot of guess work on your part.

[ravenstorm]

Okay thanks, didnt think it would be that easy lol

[arakish]

...for example is a mark 6 autocannon the equivalent of say a 25mm autocannon...

IMHO, this example would be at least a Mark 10 Autocannon, if not a Mark 20.  25mm is a BIG bullet, diameter wise.

This may be incorrect, but for slug throwing weapons, I use 2.5mm for each Mark number (Mark 1 = 2.5mm, Mark 5 = 12.5mm, Mark 50 = 125mm, etc.).

The battleship Missouri's main rifles (18 inches) would be Mark 182 (about 460mm)!!  However, logic and best judgment should also be used.

For energy projection weapons, well...  I don't really have any standard except the higher the Mark number, the more energy/power there is in the beam (and that is more or less a Duh.).

rmfr

[ravenstorm]

Thanks again, but I was kinda trying to convert Heavy Gear weapons to Spacemaster and as the biggest caliber projectile weapon in Heavy Gear is the 200mm Field Cannon, I made that Mark 50.

As for 25mm being Mark 10, well I was going on the basis that in the Spacemaster 2nd Edition book, a 10mm MG is Mark 3 and a 12mm HMG is Mark 4, so maybe a 25mm Autocannon would be more a Mark 8/9 weapon instead of the Mark 6 I originally thought

[markc]

 In the way past there was to be a RMSS Arms Law: Heavy Weapons but I think it fell through do to a shake up at ICE in the way past.
MDC

[Ynglaur]

Fun trivia: the various 1st edition products reference weapons with Mark #'s above 50.  Nothing in 2nd edition does, however.

Personally, given the volumes (sizes) of the weapons in Armored Assault and Star Strike, I'd say modern weapons are in the Mk.6 to Mk.12 range or so; maybe Mk.15 or even 20 for very large artillery pieces.  Mk.6 for a 20mm or 25mm cannon "feels" about right.  Mk.10 for a modern 120mm (or 105mm if you're feeling generous).

Just my 2 elmonits, of course.

[ravenstorm]

Well, after doing a bit of research both on the internet and with 2 other rp games i have with construction rules for weapons, it seems a 25mm autocannon, on average, has a weight of around 120 kg...which doesnt help seeing as a Mark 6 autocannon is Spacemaster 2nd Edition has a volume of 6 cumets (or about 2 mt if you follow the rule of multiplying the weight by 3 to get the volume) or 5 mt for a Mark 6 autocannon at TL19 using Spacemaster Privateers...so looks like im gonna have to do a bit of tweaking with the Spacemaster construction rules

[GrumpyOldFart]

it seems a 25mm autocannon, on average, has a weight of around 120 kg...which doesnt help seeing as a Mark 6 autocannon is Spacemaster 2nd Edition has a volume of 6 cumets (or about 2 mt if you follow the rule of multiplying the weight by 3 to get the volume) or 5 mt for a Mark 6 autocannon at TL19 using Spacemaster Privateers

Check and be sure whether either or both (mm vs. Mark) include weight/volume of ammo storage. I won't claim to know, but I bet the weight and volume of the magazine for a modern shipboard autocannon is greater than the weight and volume of the gun itself. That's probably not true of land vehicle mounted weapons, but 1) they have much greater space and weight constraints than a ship and 2) much shorter operating range and thus less need to have all the ammo they could possibly require ever.

[providence13]

http://www.btrc.net/3g3

I'll always back this book as a great resource for RL conversions. At least it approximates them well, IMHO.
There are also great examples of different game system conversions.

Need the energy requirements of a 2100AD LASER weapon, or the torque on a trebuchet, it's in there.
How much heat is produced by energy weapon inefficiency?
Is it even possible to have a gas light era energy weapon? It could have been possible, if not probable.

Even with this excellent material, you'll have to get a rough range for a SpaM table.

[Ynglaur]

I've come to strongly dislike the cumet system for SpaceMaster.  It ignores the mass of armor almost entirely, instead factoring them into the combat tables as de facto quickness penalties: just like the base game.  In both 1st and 2nd editions, SpaceMaster did a poor job of representing that middle range of weapons (14.5mm machineguns, light autocannons, etc.).

Personally, I think a better representation of volume would be Mk. * (Mk.^2/10).  This makes a Mk.6 come in at 3.6 cumets, or 1.2 metric tons,  but keeps Mk.10, 20, 30, 40, and 50 the same.  Then again, I always envisioned a 1000-result critical table (1d1000)...I probably overcomplicate things.

[markc]

 What you might do is done another 3 conversions and see if you can draw a correlation between just how far off the SM (insert version) numbers are. That is to say if all 3 weapons are about a factor of 15 off mass then just divide the mass given by 15.
MDC

[ravenstorm]

Well idk, im sure i'll figure something out but thanks for all your comments so far....

although i have to say, whats with the high price tags for all the vehicle weapons in Privateers??? Even the compact autocannon is 1.1 million!!

I think i might have ago at rewriting a lot of it myself 

[Ynglaur]

The funniest is the old SM adventure modules.  I think I figured out once that even if you completed every single adventure in every module, you wouldn't have enough elmonits for even a small starship.

[markc]

 Ravenstorm,
 BTW you said you were looking for a conversion to Heavy Gear but what are you converting the weapons for? IE for heavy weapons to attack personal? For heavy weapons to attack Vee's?


 A thought I had last night is that if you had AL: FA you could look at the Browning 2M HMG chart and just use a multiple of that damage to replicate a larger round hitting a person. IIRC in most cases the target is going to be pulp or at least if you hit a location that location is going to be so shattered from the impact that the target will die of shock very quickly (hopefully).


MDC


 Also The SM:P Equipment Man. has charts that give the various ME (Muzzel Energy charts in AL: Firearms) for various tech levels. This might be of some help someway.

[Ynglaur]

Confirming that a .50 caliber round hitting an unarmored person does horrible things to the target's bodily structure.  Even so-called "glancing" blows tend to be lethal.

[ravenstorm]

Ravenstorm,
 BTW you said you were looking for a conversion to Heavy Gear but what are you converting the weapons for? IE for heavy weapons to attack personal? For heavy weapons to attack Vee's?

Well, it was really for Vehicle vs Vehicle

[markc]

   Ok I did not sleep a lot last night and got out my old copy of Heavy Gear 2 I picked up used in the Bay Area. I noticed that the system is very free flowing in design (I have the Terran Source book) with no design rules dealing with weight-space for equipment.


1)Besides the point above do you have any of the other weapons mapped out to MK#'s?
2)What system are you going to use, SM2 or SM:P?
3)How much tech growth do you want to plan on? Is the game going to be long term with tech levels changing or new techs being introduced? (If no then it is not such a big thing IMHO if the 20mm cannon is one or two MK#'s off. If it is a long term game with weapon tech growth then it is more important what MK# you assign to the 20mm cannon.


 In the Armored Assault craft book (I do not remember the name right now, I think it is Armored Reserves) it deals with one advanced MIRC (Heavy Gear) that basically divides all/most mass's by 10.


Note: I have 2nd edition and the rules you have might have changed things from my version.


MDC

[JimiSue]

In both 1st and 2nd editions, SpaceMaster did a poor job of representing that middle range of weapons (14.5mm machineguns, light autocannons, etc.).

I strongly suspect this was done for playability. I have an armsman PC in my group whose favourite weapon is the 5mm LMG. Even though it's the smallest machine gun and he is still only level 5, he can lay waste to a combat field quite easily. I've been able to constrain him slightly by requiring minimal deaths while they are in the city but I can't do that forever! Higher mark machine guns would be so disruptive to the mechanics of the game they would be even more unbalancing.

Worth noting also that the higher the mark number in SM2, the less able the weapon is to hit small targets - so the mark 182 weapons mentioned above probably couldn't hit the broadside of a barn with any accuracy - they would need a significant target (like a similar sized ship) to be of much use. Note - not saying that's who it is in real life as I'm not a modern weapons expert, just saying that's how it is in SM!

[Marc R]

I tend to scale back heavy weapons not on the tables, but in law enforcement. . .along the lines of "And why do you have a 14.5mm machinegun in the back of your grav truck boyo?" and/or the whole "They're charging you as a terrorist mr Smith, because they caught you with a heavy machinegun in the financial district of the capitol, and they don't believe your story about shape changing aliens."

That tends to be true across the board from modern to sci-fi. . . .and gets more problematic with the more heinous man portable energy weapons, since at least a 14.5mm machinegun is a trifle heavy to casually carry and shoulder fire.