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15mm & 20mm Railguns (early Gauss Rifles)

sabredog

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OK, this is what I get for thinking out loud on the forums instead of finishing up what I was doing before dumping it on the net. What's here is different than the thread I started last, sorry, if anyone wants to delete the other one..? ....I'll add the stats for CT after dinner.

Here's two early (TL-8/10) railgun type gauss weapons developed along the lines of fleshing out the history of these things for my campaign, but also to fill some of the lower tech gaps. Mass driver technology is supposed to start becoming available per Striker at TL-8, so if I figure a serious step at every two levels then I have gauss rifles starting as railguns on the squad or platoon level, then getting progressively smaller after that for individual use as a battle rifle.

Just my thoughts, but here I go.



15mm Railgun (1st Gen Gauss Rifle)

1stGenRailgunGuassRifle.jpg


The first generation of gauss rifles come in at TL-8 with the 15mm Materials Demolition Weapon, otherwise known and operated at the first man-portable railgun. The weapon is designed to throw a heavy, armor penetrating slug downrange at high velocity and with a minimum of drop. It has similar damage, range, and armor penetrating statistics as the earlier Light Assault Gun does, but both the gun and ammunition are lighter since the rounds don’t require propellant and the gun’s construction is simpler and uses more composites.

The sabot round accelerates the length of the two rails with spin imparted by fins when the sabot is dropped. The rounds come in solid tungsten AP darts or kinetic energy armor penetrator-high explosive (KEAPER). High explosive –armor piercing (HEAP) rounds were found to not function well given the extremely high velocity of the weapon which caused them to merely shatter on impact with a hard target.

The weapon causes no heat signature , but the rounds do make a distinctive crack when leaving the rails towards the target. Nonetheless, the weapon is far stealthier as a sniper weapon than CPR designs that were equipped with suppressors.

To power the weapon a laser carbine power pack is used to provide enough power for 20 shots. A 10 round box magazine is inserted behind the pistol grip while the power cable is connected at a jack in front of the trigger guard. The weapon comes equipped with a scope, bipod, and collapsible stock.
Length: 850mm, Weight, Unloaded: 3500grams (Magazine 300 grams). Base price: Cr9,000 (Magazine 300Cr ). Tech Level 8


20mm Railgun (2nd Gen Gauss Rifle)
2ndGenRailgunGuassRifle.jpg


The second generation of gauss rifles is the TL-10 20mm Squad Support Gun (SSG-20r). This weapon development incorporated lighter materials with a more efficient railgun acceleration system to propel a 20mm slug at near hyper-velocity. The weapon requires the use of a laser rifle power pack jacked into the socket in front of the trigger guard which powers the weapon for 40 shots. The 10 round box magazine is inserted behind the pistol grip. The operator fires the weapon from a prone or rest position using the bipod and included battlesight (image enhancement and telescopic).

The weapon uses fin-stabilized discarding sabot armor-penetrators, KEAPER, and HE rounds. It fires either single shots or a 5 round auto-burst. Care must be taken when firing in burst mode not to overheat the mag-rails or they can warp, rendering the weapon useless since it will require an armorer’s shop to replace and align rails. This is why the magazine capacity was decided to be limited to 10 rounds; the extra time taken to reload also for cooling between bursts. Mainly, the weapon is most useful in single shot mode against light armored vehicles and reinforced positions by taking advantage of the greater velocity and kinetic impact of the penetrator rounds than can be fired by other man-portable weapons other than ATGM’s. When HE rounds are used the operator adjusts the weapon's velocity to ensure proper detonation. The best use of these rounds is for area suppression and when firing into buildings and soft targets.
Length: 1,000mm, Weight, Unloaded: 3,700 grams (Magazine 400gms). Base price: Cr10,000 (Magazine 250Cr) Tech Level 10
 
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15mm Material Demolition Gun (MDG Mk-6) Tl-8

Range Modifiers

Close Short Medium Long VLong
KEAP -6 0 +3 +2 -1 3D6
KEAPER -6 0 +3 +1 -2 3D6+4


Armor Modifiers

None/Jack Mesh Cloth Reflec Ablat Combat
KEAP +4 +3 +2 +4 +4 +1
KEAPER +3 +1 +1 +4 +4 0

Dexterity Modifiers Required Advantageous
Level DM Level DM
6 -1 9 +2







20mm Squad Support Gun (SSG-20r) TL-10

Range Modifiers

Close Short Medium Long VLong
KEAP -7/-8 0/-1 +4/+5 +3/+4 0/+1 4D6
KEAPER -7/-8 0/-1 +4/+5 +2+3 -1/0 4D6+4
HE no no +2/+4 +1/+3 -1/+1 3D6


Armor Modifiers

None/Jack Mesh Cloth Reflec Ablat Combat
KEAP +4/+6 +3/+5 +2/+3 +4/+6 +4/+5 +1/+3
KEAPER +3/+5 +1/+3 +1/+2 +4/+6 +4/+5 0/+1
HE +4/+6 +3/+4 0/+1 +4/+6 +3/+4 -1/0

Dexterity Modifiers Required Advantageous
Level DM Level DM
7 -1 10 +2
 
Early Gauss Guns

Re: Overheating problems
Have you thought of enclosing the rails in a sleeve of some sort (weight issues?) and having a small canister of inert gas (Co2 cartridge) to 'purge' the rails and provide cooling?
 
Enclosures: weight, mainly. The rounds don't need to be contained because of the magnetic field, and as a military weapon aesthetics are not really a concern. I thought they might snag on something, but the barrel of any gun will do that and given the specialist role of these there won't be very many out there anyway.

Although a sleeve could be added for protecting the rails that would be lightweight. Just some plastic sleeve. But, for illustrative purposes I wanted to show the rails, too.

Heat: Hadn't thought of that, but it might be a good reason why the rails are exposed even if that is only a field-mod by the operator. But a chill can like the ones used by combat environment suits might be applicable.

But the problem with shooting cold air over the rails might be that they could be warped or cracked. But I suppose that's where a materials engineer would come in and I'm just a humble Trav ref.
 
Shadowrun 4th edition had a Gauss Assault Cannon in the book Arsenal. Mind that an Assault Cannon is at least an LAG.

Link to be edited in when possessed.
 
Regrettably I don't have Shadowrun - never could get into the whole orc n' elf cyberpunk thing. Played Cyberpunk, 1st ed., though.

These are just to fill some developmental gaps in gauss rifle tech. I figure that as the technology is perfected the rifles will decrease in size as they increase in energy efficiency and capability. So before they become personal weapons they start out, as a lot of slugthrowers seem to, as a support or specialist type of weapon.

The 20mm version is fairly redundant when compared to LAG's but since it's zoomy and new it is out there as a step towards the TL-12 personal version (and the TL-12 G-SAW support gun). I also have them getting just a little lighter at TL-13, and with an underbarrel, magazine-fed (5 shot) 20mm RAM launcher that does the same damage as a 40mm version, but the gun is the same as far as performance. It's just lighter, a little shorter, and has a larger magazine (80 rounds instead of 40).

But at TL-13 they hit their wall of capability since at that point the plasma weapons are showing more promise as a personal weapon (PGMP-13) instead of as a heavy support gun that only fires every other round (PGMP-12), and battle dress means weapon size is not as important as before.
 
So here is my TL-12 interpretation of the gauss rifle: shoot-through greande launcher, 40 round mag, etc..
GaussRifle-1.jpg


This is the smaller, lighter TL-13 version with 20mm RAM launcher (no magazine-fed RAM launcher in it since I need to fix that but you get the idea):
GaussRiflemod2-1.jpg


And here is a TL-11 "Sniper" version that is, again, a developmental step from specialist weapon to the TL-12 practical battle rifle:
GaussRifleSniper.jpg
 
I don't see why the TL-12 version would have a shoot-through GL. Wouldn't it just have some sort of underbarrel gauss GL?

And that's something Traveller needs: a gauss grenade launcher. It ought to be TL-11 or so. And a gauss mortar would be TL 10.
 
I don't see why the TL-12 version would have a shoot-through GL. Wouldn't it just have some sort of underbarrel gauss GL?

And that's something Traveller needs: a gauss grenade launcher. It ought to be TL-11 or so. And a gauss mortar would be TL 10.
I've actually believed that for a long time, and I think I posed something like that some time after I joined the forum. I'm not sure if anyone ever followed up with the idea.
 
I don't see why the TL-12 version would have a shoot-through GL. Wouldn't it just have some sort of underbarrel gauss GL?

It's just another of those weird inconsistencies with how technology has progressed versus how the game designers imagined it would in the '70's. I keep it for variety and because I don't want to have to rewrite the entire rules just to "fix" everything every couple of years.
 
It's just another of those weird inconsistencies with how technology has progressed versus how the game designers imagined it would in the '70's. I keep it for variety and because I don't want to have to rewrite the entire rules just to "fix" everything every couple of years.

It might also be that Mr. Miller and co. simply didn't think about it (high-tech GLs). But that's where fans come in.:)
 
And also tech level variances --

so if a world say is at TL 8 in energy -- it could be at TL 12 in computers/electronics or TL 10 in Medicine or TL 7 in land vehicles - and so on

so no world is just stuck at a acertain TL -- the variation within it -- makes the world interesting.
 
Railgun or Gauss gun

I wanted to know want to know sabredog. You draw railgun or gauss gun, because that is not the same thing at all. The railgun use lorentz force to accelerate a conductor projectile and can also be call electric gun, while the gauss gun (or coilgun or electromagnetic gun) use the electromagnetic force to accelerate a ferromagnetic projectile.

Your gun look very much like a railgun, while the TL-11/12/13 series look more like multistage coilgun, with the coils around the cannon.

Also increasing the bore caliber of a railgun do not change the power of your shot at all. It's the power input and the ratio of bore diameter vs diameter of your rails that change the efficiency of the railgun. But if you keep the same ratio a 1mm caliber railgun or a 90mm railgun with the same power input will produce the same kinetic energy. The only difference is a trade between projectile mass and projectile velocity. The 1mm will be a very fast low mass projectile very penetrating while the 90mm will have moderate to velocity with heavy projectile.

Last thing, where is the batteries and capacitors of your guns. They should take more space than your magazine in your design.

I like your rail design, expose like that. Really nice for the overheating problem, especially the second gen. gun.
 
I wanted to know want to know sabredog. You draw railgun or gauss gun, because that is not the same thing at all. The railgun use lorentz force to accelerate a conductor projectile and can also be call electric gun, while the gauss gun (or coilgun or electromagnetic gun) use the electromagnetic force to accelerate a ferromagnetic projectile.

Your gun look very much like a railgun, while the TL-11/12/13 series look more like multistage coilgun, with the coils around the cannon.

They are railguns...which is why I call them that. I parenthesize the "gauss rifle" name because that is what the higher TL versions are, and what most people know them by.

Also increasing the bore caliber of a railgun do not change the power of your shot at all. It's the power input and the ratio of bore diameter vs diameter of your rails that change the efficiency of the railgun. But if you keep the same ratio a 1mm caliber railgun or a 90mm railgun with the same power input will produce the same kinetic energy. The only difference is a trade between projectile mass and projectile velocity. The 1mm will be a very fast low mass projectile very penetrating while the 90mm will have moderate to velocity with heavy projectile.

That would have to be a huge amount of power...more than available for a man-portable weapon...to create the same kinetic energy with 1mm round as a 9cm round. Penetration doesn't always equate to kinetic killing power for anti-materials weapons - which is primarily what these are for. That and area suppression.

Besides, I have the larger round for carrying explosive warheads since the thing may have a high velocity it isn't realistically going to fire some anti-armor round with the velocity an APFSDSDU round will need unless the recoil was such that the operator couldn't safely fire it. And lower tech is clunkier.

And lastly, if I was a real engineer and weapons designer my gear would be more accurate, but I only play one in Traveller. ;)

Last thing, where is the batteries and capacitors of your guns. They should take more space than your magazine in your design.

You probably missed it in the writeup but the magazines only carry the rounds to be fired - the weapons are powered by backpacks similar to those used by energy weapons.

I like your rail design, expose like that. Really nice for the overheating problem, especially the second gen. gun.

Thanks! ;)
 
That would have to be a huge amount of power...more than available for a man-portable weapon...to create the same kinetic energy with 1mm round as a 9cm round.

No, that my point. For the same power input, the mass of the projectile doesn't change the kinetic energy, it only change the muzzle velocity of your projectile. A 1 gram projectile will need the same input energy to reach the same kinetic energy that the 1 kg projectile. It will only go faster.

I have the larger round for carrying explosive warheads

I'm not sure, maybe there are a way to make that secure, but a several ampere will pass thought you projectile and may detonate your warhead inside your gun.

You probably missed it in the writeup but the magazines only carry the rounds to be fired - the weapons are powered by backpacks similar to those used by energy weapons.

I know that. It's just that the backpacks should be apparent because they will propably take a major part of the weight and volume of the railgun. Especially will man-portable weapon, because the efficiency a any electric system (like the railgun) decrease while the current decrease.

Man-portable = less current = less efficiency = bigger ratio battery/everything else
 
No, that my point. For the same power input, the mass of the projectile doesn't change the kinetic energy, it only change the muzzle velocity of your projectile. A 1 gram projectile will need the same input energy to reach the same kinetic energy that the 1 kg projectile. It will only go faster.

OK, I see what you are saying now. Yeah, that occurred to me, too. But I wasn't sure that just increasing the velocity would be as practical as increasing the mass thrown as well as a small increase in velocity. But, like I said: I'm not really an expert - a lot of these sort of things I come up with just as a "what if" and I don't do the math.


I'm not sure, maybe there are a way to make that secure, but a several ampere will pass thought you projectile and may detonate your warhead inside your gun.

Maybe, but given that one manufacturer has already come up with a way to stack rounds in one barrel and fire them in a controlled sequence electrically, I figure a non-electrically primed warhead could pass through a magnetic field without exploding.

Check out Metalstorm for what is being done today with what I described above: http://www.metalstorm.com/content/view/37/92/

Among other things here is a 3-shot grenade launcher that can be fired one round at a time and they are all fired with electric priming. The grenades are stacked in the barrel one behind the other. They also make pistols and othe weapons the same way.

I know that. It's just that the backpacks should be apparent because they will propably take a major part of the weight and volume of the railgun. Especially will man-portable weapon, because the efficiency a any electric system (like the railgun) decrease while the current decrease.

Man-portable = less current = less efficiency = bigger ratio battery/everything else

You're right - they would take up a lot of the combined "effective" weight of the system. I just didn't list their stats because they are already in the rule books. And I also figured that since those same backpacks are available at those TL's already that they are probably a standardized design and the makers of the railguns would base their specs for development on them rather than come up with something else.


And sorry it took so long to respond - I haven't even looked at these forums for more than passing glance for a while now while I've been taking classes.
 
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