How heavy is a Fusion Gun?

[Wade Grant]

If this has been discussed before could someone point me in the right direction please?

On page 200 a fgmp14 weighs 1kg, but the ammo/powerpack weighs 9kg? Is this correct and fgmps are hightech "grease guns" where the ammo is the real system and the other part is just the trigger? I have the same problem with the fgmp15 also..a 1 kg unit needs to generate, contain, and direct a fusion reaction, and mount a anti-grav generator to make it lighter. If anyone needs anti-grav for a 1kg weapon i suggest a more strenuous workout...pour the bear from the can into a mug that will excerise the arm muscles more.

I personally think that they are missing a 'zero' in there.

 

[snrdg082102]

Hello Wade Grant,

T20 is based on the material designed for Classic Traveller. CT Book 4 Mecenary (copyright 1978) p. 38 agrees that the weight of the FGMP-14 and FGMP-15 are as published in The THB table on p. 200. CT: Stiker Book 3 Individual Weapons: Energy Weapons Table Copyright 1981 5th ed) on p. 31 indicates the weight of a FGMP-14 is 10kg and the power pack is 80kg. The FGMP-15/power pack weighs 10/20 kgs with the gravitic generator off and 1/2 kgs with the generator on. MegaTraveller: Imperial Encyclopedia (copyright 1987 1st ed) p. 75 Has the FGMP-14/power pack weight as 10/9 kg. The FGMP-15 weighs the same as indicated for Striker.

The FGMP-14 requires the user to be in BD.

Originally posted by Wade Grant:
If this has been discussed before could someone point me in the right direction please?

On page 200 a fgmp14 weighs 1kg, but the ammo/powerpack weighs 9kg? Is this correct and fgmps are hightech "grease guns" where the ammo is the real system and the other part is just the trigger? I have the same problem with the fgmp15 also..a 1 kg unit needs to generate, contain, and direct a fusion reaction, and mount a anti-grav generator to make it lighter. If anyone needs anti-grav for a 1kg weapon i suggest a more strenuous workout...pour the bear from the can into a mug that will excerise the arm muscles more.

I personally think that they are missing a 'zero' in there.

 

[justacaveman]

I asked this quetion before, and the official answer from Hunter was that the THB values were correct.

Personally I think the Striker values make more sense.

 

[kaladorn]

Originally posted by Wade Grant:
If anyone needs anti-grav for a 1kg weapon i suggest a more strenuous workout...pour the bear from the can into a mug that will excerise the arm muscles more.

I'm guessing that pouring "bear" from a can would in fact be a workout of a very formidable form. Especially if said "bear" was not happy about having been canned.

 

[kaladorn]

80kg seems a bit much to make it past *any* procurement board.

Now, there is some fusion gun that is usable (or is it a plasma gun) without battle dress... that pretty much requires a weight no heavier than about 6 kg in the main part of the weapon, if one is going to use it like a standard 'long arm'.

Once you're in battle dress, you still don't do away with inertia, with momentum, or a number of other concerns. So having a 90kg weapons system still seems problematic. And what is it made of? Unobtainium?

I agree with your supposition that a 1 kg weapon hardly merits gravitic assist, but perhaps that is the post gravitic assist weight? And 9 kg, though heavy, doesn't seem impossible for a power pack. I wouldn't want a 10kg weapon that I had to manouver around, especially if I had to do any kind of urban operations where CQB could result and speed could be a key item - in that case, a 10kg weapon (even driven by BD) will be too slow IMO.

 

[vegascat]

I see the gravatic assist to control the recoil in the FGMP 15, and to make it easier to aim. For the FGMP 14, you must be in BD to handle the recoil. You could explain to players that it is like holding a burning rocket, and standing in front of it would be similar.

 

[justacaveman]

An FGMP-14 is only usable by someone in Battle Dress (300kg), so an 80kg power-pack doesn't seem that excessive to me. Your typical infantryman carries a 25 kg backpack plus weapons and ammo when marching (About 35kg total).

An FGMP-14 will do almost as much damage to a vehicle as a 4,000 kg light fusion gun, and has a 40 shot power-pack. If you want something lighter, you could always reduce the number of shots.

 

[Tanuki]

Originally posted by LordRhys:
An FGMP-14 is only usable by someone in Battle Dress (300kg), so an 80kg power-pack doesn't seem that excessive to me. Your typical infantryman carries a 25 kg backpack plus weapons and ammo when marching (About 35kg total).

An FGMP-14 will do almost as much damage to a vehicle as a 4,000 kg light fusion gun, and has a 40 shot power-pack. If you want something lighter, you could always reduce the number of shots.

This might be of interest in this discussion:
http://www.travellerrpg.com/cgi-bin/Trav/CotI/Discuss/ultimatebb.cgi?ubb=get_topic;f=9;t=000105;p=1#000009

 

[kaladorn]

Originally posted by LordRhys:
Your typical infantryman carries a 25 kg backpack plus weapons and ammo when marching (About 35kg total).

A 25 kg pack was a light pack!

But also our LBE had a capability to execute an emergency breakaway, and where possible we really loved to shuck down to nothing more than webbing with a few necessities (ammo, med stuff, dry socks, etc) which was way less. The pack did slow you down and made you more awkward and made you an easier target. That's not a good thing.

And if your *weapon* does that alone, before you add in food, medical stuff, commo, etc, then you're in trouble.

 

[justacaveman]

Battle Dress already has built-in commo, nightvision, and a 14vl cargo space (70 liters).

While the design rules state that the weight of a vehicle is 1kg per vl, this does not take into account the weight of armor. Adding very light armor (10kg/vl) to the weight of TL13 Battle Dress gives a weight of 960kg.

A 1-ton vehicle wielding a 10kg weapon (w/20 STR), and carrying a an 80kg backpack is not excessive. The total weight would be the equivalent of an infantryman carrying a light machinegun and ammo.

This is a weapon that is designed to take out tanks, and has 40 shots to do it with. A average character wearing TL14 Combat Armor (AR 8)that is hit by an FGMP-14 will be severely injured and unconcious or dead unless they're very lucky(roll the dice and see the results). And if an FGMP-15 is used (and it's much lighter), the target will be killed almost every time.

You don't need weapons the size of an M16A2 doing this kind of damage in any campaign. If the were really that small, the military would merely make them bigger so that they would do more damage to vehicles (yet they already do more damage than vehicle weapons 10 times their size).

 

[kaladorn]

Originally posted by LordRhys:
[QB] Battle Dress already has built-in commo, nightvision, and a 14vl cargo space (70 liters).

While the design rules state that the weight of a vehicle is 1kg per vl, this does not take into account the weight of armor. Adding very light armor (10kg/vl) to the weight of TL13 Battle Dress gives a weight of 960kg.

I suppose this is T20 you're talking about? (I'm not sure that this has always been the case)

A 1-ton vehicle wielding a 10kg weapon (w/20 STR), and carrying a an 80kg backpack is not excessive. The total weight would be the equivalent of an infantryman carrying a light machinegun and ammo.

Yes, it is.

Walk through a building.... and end up in the basement. Your ground pressure (and your weight) will result in many areas or urban territory and of rural territory (swamps, plowed fields, wet or churned ground, mucky stream beds, etc) being utterly off limits to anything weighing 2000 lbs!

And an LMG is *NOT* a suitable weapon for CQB. Some CQ operators don't even use long arms - they stick exclusively with pistols - sufficiently deadly at the ranges involved, and far far faster to get on target and to respond to new and unexpected threats. Failing that, they use shortened carbines and short SMGs. And none of these is likly to mass more than 3-4 kgs.

An LMG is not sufficiently quick in close quarters. It is also too long and unwieldy. Ignoring the length issue since FGMP length is questionable, I'll just focus on the responsiveness/manouverability issue: A 10kg weapon is not sufficiently manouverable for CQ.

This is a weapon that is designed to take out tanks, and has 40 shots to do it with.

Making it inadequate for use in urban terrain, anyplace you might not want to kill everything (ie civilians are nearby or friendlies) and making it inadequate for use in cramped shipboard conditions.

A average character wearing TL14 Combat Armor (AR 8)that is hit by an FGMP-14 will be severely injured and unconcious or dead unless they're very lucky(roll the dice and see the results). And if an FGMP-15 is used (and it's much lighter), the target will be killed almost every time.

Yes. And nearby equipment, walls, floors, etc. will be destroyed either by the explosion or the heat and the radiation will damage electronics not killed by the explosion or heat. Not exactly useful for protecting anything you care about or conducive to the buildings you will find yourself in during OOTW or any kind of MOUT.

You don't need weapons the size of an M16A2 doing this kind of damage in any campaign. If the were really that small, the military would merely make them bigger so that they would do more damage to vehicles (yet they already do more damage than vehicle weapons 10 times their size).

This analysis selectively ignores many facts.

In areas where you care about your surroundings, you're going to want to use a more precise weapon with fewer collateral effects (Queue high tech laser rifle).

In tight areas (shipboard or in buildings), the lumbering battle dress is going to be very awkward and having a weapon that blows the crap out of nearby controls and electronics, walls, floors, and civilians seems rather self-defeating.

And anytime you have to fight in a rapid reaction environment, whipping around a 10kg weapon is gonna be slower than the 1kg weapon. And if the 1kg weapon can shoot first, it'll probably win. (Laser rifle will penetrate most battle dress)

1000 kgs is a stupid weight for battle dress. 90 kg is a stupid weight for a weapon. Of course, this is entirely IMO.

I think battle dress should weigh in (at max) at about 100kg and a weapons system at max at about 10-15 kgs, and if you need it for close quarters, much less than that.

But, its your TU. And if you like the T20 construction rules (argh....), fill your boots.

 

[justacaveman]

The Topic Is: "How heavy is a Fusion Gun?"

The Topic Is Not: "What weapon is best for close quarters combat?"


In T20, FGMP's are support weapons that are carried by soldiers in walking tanks (Battle Dress).

TL13 Battle Dress in T20 has a volume of 300vl. This equals 1500 liters in the TA4/TA6 design rules. 1500 liters is 1.5 cubic meters (a cube over 3 feet wide by 3 feet deep by almost 5 feet high. Make it man-shaped, and you get a 7 foot tall walking tank. This thing is going to barely fit down ship cooridors, and will tend to get stuck in hatches, etc.. Of the 1500 liters of volume in this vehicle, 330 liters are devoted to armor. A conservative estimate of armor weight would be about 5kg per liter (Steel is about 7kg per liter.), making the total weight of the Battle Dress a realistic 1950kg (about 2 Metric tons), or 4,290 lbs.

Using the T20/D20 size scales, TL13 Battle Dress is listed as Size L, much larger than a human (Size M), and as large as an Ursa (Uplifted Grizzly Bear).

CQB soldiers would be using Gauss SMG's and wearing Combat Armor or lighter protection, not in man-shaped tanks carrying anti-tank weapons.

 

[kaladorn]

Originally posted by LordRhys:
The Topic Is: "How heavy is a Fusion Gun?"

The Topic Is Not: "What weapon is best for close quarters combat?"

Well, it isn't explicit (though upon re-reading it may be implicit) that this is a T20 discussion from the original post. I do see it is posted in the T20 section (sorry, I arrived here from the 'active topics' area and missed that small print at the top)

And in other versions of traveller, there is no such thing as a gauss SMG and battle dress is worn by (in varying descriptions) most or all of the Imperial Marines and therefore is not a support item and probably doesn't weigh what it does in T20. And in fact, one of the fusion guns (or is it a PGMP?) can be used by people NOT in battle dress.

Anyway, if you want to talk strictly about T20, I'll leave you to it.

 

[justacaveman]

The Gauss SMG appears in several other versions of Traveller, including CT.

The PGMP-12, PGMP-14, and the FGMP-15 are all usable by people not wearing Battle Dress. The PGMP-12 is an early plasma weapon, and you do need to be wearing Combat Armor to protect yourself from weapon side effects. The PGMP-14, and FGMP-15 are gravitic assisted weapons, and are the most powerful weapons available to infantry at their respective Tech Levels. These particular weapons outclassed every other weapon available to infantry in most versions of Traveller. They were designed as anti-armor weapons, and no starship captain in his right mind would allow one to be used onboard ship. They were quite capable of punching through the hull in most versions of Traveller, and the collateral damage associated with these weapons would prohibit their use around anything you wanted to keep intact for later use (like the ship).

The T20 designers decided that Battle Dress was a vehicle, and that changes the use of Battle Dress tremendously. In the standard T20 rules most infantry wepons can't harm a heavily armored vehicle at all on a normal hit. However, when a critical hit is scored, just about any weapon can severely almost any vehicle without regard to the level of armor. I've had to adopt house rules to address the critical hit problems in the standard rules.

 

[kaladorn]

Originally posted by LordRhys:
The Gauss SMG appears in several other versions of Traveller, including CT.

Please cite a CT reference for the Gauss SMG.
Or an MT reference.

It may exist in GT and T20. Maybe even T4. But I do not recall ever seeing it in CT or MT.

I'm always willing to learn that I am wrong, but I would love to see a specific citation to back up this claim.

The PGMP-12, PGMP-14, and the FGMP-15 are all usable by people not wearing Battle Dress. The PGMP-12 is an early plasma weapon, and you do need to be wearing Combat Armor to protect yourself from weapon side effects. The PGMP-14, and FGMP-15 are gravitic assisted weapons, and are the most powerful weapons available to infantry at their respective Tech Levels. These particular weapons outclassed every other weapon available to infantry in most versions of Traveller. They were designed as anti-armor weapons, and no starship captain in his right mind would allow one to be used onboard ship. They were quite capable of punching through the hull in most versions of Traveller, and the collateral damage associated with these weapons would prohibit their use around anything you wanted to keep intact for later use (like the ship).

I don't think you are correct here, at least not from an MT perspective (and I wouldn't be surprised if this was true in AHL too, and I don't believe (though I'd have to go grab the rulebook) that Snapshot covered these and I don't recall anything in books 1-5 that would suggest whether an FGMP would actually penetrate a starship hull or not in CT). Starship armour 0 was armour value 40 in MT. No hand held FGMP or PGMP could reach this level of penetration.

Now, it would make a mockery of most internal walls and doors, I concede. But not the hull or pressure bulkeads and hatches.

The T20 designers decided that Battle Dress was a vehicle, and that changes the use of Battle Dress tremendously. In the standard T20 rules most infantry wepons can't harm a heavily armored vehicle at all on a normal hit. However, when a critical hit is scored, just about any weapon can severely almost any vehicle without regard to the level of armor. I've had to adopt house rules to address the critical hit problems in the standard rules.

On the one hand, the idea of mostly impervious battle dress makes sense (from the perspective of weapons designers and those paying for military equipment). OTOH, from the perspective of a ref running a game, this can be... quite a bane. So one needs to have adequate countermeasures available to avoid the perils to the game this may cause. So I can understand that aspect of this quite well.

 

[justacaveman]

I believe that the Gauss SMG could be found in Striker, possibly in Mercenary. It's been a long time since I've played these versions, they were available in TNE, and T4. And the Gauss pistol has always been capable of firing bursts, and basically is an SMG (You can find it in TA1).

Hull penetration by an FGMP-15 may not be possible in all versions of Traveller (it's been 15+ years for some versions for me), but it is a possibility in some. And if you use the standard T20 rules, any Critical Hit by an FGMP-15 on a ship will cause internal damage (i.e. hull penetration).

I'm not trying to be contentious, I'm playing T20 and need to look at things from that perspective. I have played every version of Traveller ever made, and while T20 has some game mechanics problems, they can be worked out with a few house rules. And I agree that the T20 version of Battle Dress is too bulky and heavy for close quarters combat, but that's what TL14 Combat Armor is for. Combat Armor may not enhance your strength, but it protects you from most small arms while providing environmental protection and sense enhancements (Just what you need for shipboard combat). Previous versions of Battle Dress were just Combat Armor with strength enhancements and additional armor for protection. In T20 you could simulate this by creating Powered Combat Armor. Add an exoskeletal strength booster, some more armor, increase the weight to 80 kg or so, and you basically have what Battle Dress originally was meant to be. I still wouldn't use high energy weapons on a ship though.

 

[kaladorn]

Originally posted by LordRhys:
[QB] I believe that the Gauss SMG could be found in Striker, possibly in Mercenary. It's been a long time since I've played these versions, they were available in TNE, and T4. And the Gauss pistol has always been capable of firing bursts, and basically is an SMG (You can find it in TA1).

I'll check Striker II (in the basement) but I don't recall seeing it in Mercenary (believe me, if it had been, I'd have seen lots of it in the many past campaigns....). But I don't ever recall seeing it there. It may well have been in TNE or later - I have all those, but have never played any of the rulesets later than MT. GT, TNE, T4, T20... I own these all as 'reference'.

And you can't *quite* call the gauss pistol an SMG. It fires bursts, but that'd be like calling the Berreta 93-R or the Stechkin an SMG. That's a pretty wide definition. They have magazines which are too small to be much of an SMG and their accuracy fired in bursts with no shoulder stock (even the Berreta has a folding optional one to address this) absolutely would suck.

A proper gauss SMG would have a folding stock, an ability to tune the weapon 'down' to fire a little slower (subsonic to help silence it) and would have far better ergonomics than a pistol in terms of controlling bursts or hitting a target accurately, and of course also have a magazine at least 2-3 times as large as that on the Gauss Pistol.

Hull penetration by an FGMP-15 may not be possible in all versions of Traveller (it's been 15+ years for some versions for me), but it is a possibility in some. And if you use the standard T20 rules, any Critical Hit by an FGMP-15 on a ship will cause internal damage (i.e. hull penetration).

Wow! That means starship hulls in T20 are kind of tinfoil like compared to the base hull in the older versions. Good to know.

I'm not trying to be contentious, I'm playing T20 and need to look at things from that perspective.

I hope I'm not coming across as contentious either. I actually want to know if I'm mistaken about things (forex the Gauss SMG) and I can only really claim expertise in the older versions.

I'm actually quite happy to be educated about the apparent power of weapons in T20. If I ever make the switch (I have though to), this kind of thing will be of immediate use.

I have played every version of Traveller ever made, and while T20 has some game mechanics problems, they can be worked out with a few house rules. And I agree that the T20 version of Battle Dress is too bulky and heavy for close quarters combat, but that's what TL14 Combat Armor is for. Combat Armor may not enhance your strength, but it protects you from most small arms while providing environmental protection and sense enhancements (Just what you need for shipboard combat).

That makes sense.

I'm just thinking that it is a bit of a change from GT which IIRC portrays every marine as a battle dress wearing beastie.

Previous versions of Battle Dress were just Combat Armor with strength enhancements and additional armor for protection.

That's a pretty accurate summary.

In T20 you could simulate this by creating Powered Combat Armor. Add an exoskeletal strength booster, some more armor, increase the weight to 80 kg or so, and you basically have what Battle Dress originally was meant to be. I still wouldn't use high energy weapons on a ship though.

Nor I.

Though using a gauss rifle or something that can't (at least in MT and I think in AHL) practically penetrate enemy battle dress or combat armour is silly. Your main weapon should match the armour you expect to engage, and if your marines have it, so probably will the enemies. So at least a TL-13 Laser Rifle or a Plasma Gun was almost required in MT in order to dent someone in high tech combat armour or battle dress.

If this has changed (ie if the gauss rifle in T20 can menace someone in high tech combat armour), then it is also a viable weapon (though the laser or an accelerator rifle make more sense in case grav plating goes down).

Neural weapons are of course the ultimate zero-recoil weapon....

 

[justacaveman]

The main reason that FGMP's are a threat to starships in T20, is the Critical Hit rules.

I've adopted house rules to reduce, but not eliminate the threat. Heavily armored ships have nothing to worry about from small arms, but ships with little or no armor need to worry a little bit.

In T20 a TL12 Gauss Rifle is a definite threat to any TL Combat Armor.

Example: The Regular Imperial Marine shown on page 424 of the THB needs to roll a 12 to hit a similarly equipped marine (TL14 Combat Armor, TL12 Gauss Rifle) with a 4-round burst for extra damage. A 15 is rolled for a normal hit and the damage dice are rolled (2d12 + 2d12 for the burst), the results are 9, 8, 5, and 3 for 25 points damage. The damage is subtracted from the marine's Stamina of 44 leaving 19 points of Stamina. The dice are compared to the Target's AR (Armor Rating) to determine Lifeblood damage. The marine has an AR of 8, so the the lowest 3 dice are removed first, leaving the 9. There are 5 more AR points left, so they are subtracted from the 9 leaving 4 points of Lifeblood damage. The marine has 14 points of Lifeblood, so he now has 10 points left. If the firing character had used armor-piercing ammo with an AP of +6, the target would have received another 6 points of lifebood damage. If the firer had scored a Critical Hit, the target would probably be unconcious, possibly dead.

If an FGMP-15 had been used, the target would probably be dead on the first normal hit (An average of 90 points of damage per normal hit), and if a Critical Hit had been scored you'd be lucky to find the target's charred remains.

 

[justacaveman]

Correction to the example above: Using the standard rules, a Critical Hit with the Gauss Rifle would kill the target. With my house rules, the target's armor is not bypassed completely, but only halved (Combat Armor is fully enclosed, so he's just probably dead.).

 

[BetterThanLife]

Anyone planning on using an FGMP (or PGMP for thatmatter) in CQB obviously doesn't want to live long. Look out for the blast radius, splash from walls and generally cumbersomeness of the system.

I do agree that 80kg is definitely a bit much for a Man portable weapon. Not just because it has to be carried but because they have to be stored, shipped, resupplied, dropped, air/dropped, maintained and generally lugged across the battlefield and space.

For CQB (Particulary aboard a Starship) use a Gauss rifle and a Bayonet.

Oh and when fighting aboard a starship Fusion guns and bulkheads don't tend to get along. (Beware explosive decompression.)

Originally posted by kaladorn:
80kg seems a bit much to make it past *any* procurement board.

Now, there is some fusion gun that is usable (or is it a plasma gun) without battle dress... that pretty much requires a weight no heavier than about 6 kg in the main part of the weapon, if one is going to use it like a standard 'long arm'.

Once you're in battle dress, you still don't do away with inertia, with momentum, or a number of other concerns. So having a 90kg weapons system still seems problematic. And what is it made of? Unobtainium?

I agree with your supposition that a 1 kg weapon hardly merits gravitic assist, but perhaps that is the post gravitic assist weight? And 9 kg, though heavy, doesn't seem impossible for a power pack. I wouldn't want a 10kg weapon that I had to manouver around, especially if I had to do any kind of urban operations where CQB could result and speed could be a key item - in that case, a 10kg weapon (even driven by BD) will be too slow IMO.