Boom Gun; Rail Gun or Conventional Artillery Piece?

[Svartalf]

Wrongo boyo.
This particular gun DOES use casings, because it is not the classical rail gun. Most rifts rail guns are magnetic machineguns, with a feed taking magnetic metal pellets at high speed into the barrel where they are accelerated and sent toward the target. They rely on swiftness of feed and sheer rate of fire for damage capacity.
The boom gun is a flechette gun : a casing, similar to a shotgun shell is loaded in advance with some 200 magnetic metal flechettes, which are sent all together at supersonic speeds. the casing is then extracted and another fed in. Not as fast as the classical machinegun, but each massed flechette shot is much more damaging than a normal burst.

The recoil comes from the supersonic shockwave of the shot... and how do you know that railguns don't have recoil? ever used one?

BTW the "smoke" from the shell case on the p 77 illo is no more than artistic licence for the cases ejection trajectory. Also, the artists that came after Kevin Long not only had no say about the game stats of the boom gun, they had no say about what it was either : the boom gun was an established game fact before they even learned of its existence, so their own conceptions are purely irrelevant. Any artist's depictions that makes one think that the boom gun would be a conventional artillery pieces comes from either of 2 possibilities :
a) artistic licence and excessive analogies. the artist does not *know* how to depict a rail gun blast, so he does as he feels and/or uses similitued with conventional guns as an analogy.
b) bad art. the art is just plain incorrect, but it looked good enough that palladium still accepted to buy it

[glitterboy2098]

a rail gun would have recoil.
basic laws of motion.
an action will have an equal and OPPOSITE reaction.
a slug being shot in one direction will cause what ever shooting it to be propelled in the other.
it has nothing to do with propellant.


as for the casing?
the Boom Gun is not a "rail gun".
technically, it is a Gauss Rifle.
a gauss rifle uses stacked electromagnetic rings around the barrel. (imagine doughnuts around a pipe.)
The BG fires 200 one inch long rods, in a Discarding Sabot casing.
the electromagnetic feild of the first ring grips the 200 rods, and as the power is transfered to each ring in turn, it accellerates. when it exits the barrel, the Sabot falls away, and the rods follow the trajectory.
the extra inches would be just thick material for the Sabot. and the thickest will have to be the section immediately ahead of the rods, as it will be absorbing much of the strees from the sudden acceleration.
at the speeds involved, (Mach 5 IIRC), friction will turn the outer layers of the material to plasma, due to the heat. (the SR-71 blackbird, travelling at mach 3, heats to several THOUSAND degree's, and only survives by using a special heat resistant titanium and heat resistant tiles similar to the shuttle's.) the plasma shrouded Sabot leaving the barrel will resemble a muzzle flare.
Sabot needs a casing to keep it together when in the ammo bin, as the sabot is designed to fall away easily. on a BG round, this is the thing resembling a shotgun base.
now, the acceleration to mach speeds is nearly instantaneous, and rips the Sabot and rods right out of the base. the heat from this will convert the outer layers of the base to plasma as well, and when ejected it will sear the air, as it cools. this produces a substance similar to smoke.

[Brian Manning]

The recoil comes from the projectile accelerating (conservation of momentum). Basically the 2lbs (I don't remember how much it weighs) projectile has to "push" off of something to get up to mach 5. Which means that same amount of force is going to be exerted on the GB itself. While I don't know how much force that is, or if the whole recoil system is even necessary, the point I wanted to bring up is that rail guns do have recoil.

As for artistic license...I can see that happening. I'm sure there are many cases where the artist added some little nozzels or tubes and Kevin Siembieda decided to give the "flavor" some functionality.

[Svartalf]

Glitterboy

You raise a point that I find highly interesting : you make a distinct difference between a gauss rifle and a rail gun.
Call me a scientific/military ignorant, I always thought rail gun was just a synonym for gauss rifle... and am not sure where the basic difference lies between a system powered by coils and one that relies on a rail.. Would you have info on this subject, or know where I could find it?

[R Ditto]

IMHO, true rail guns don't really exist in Rifts. True rail guns use a pair of rails and a round of made of conductive materials (IIRC), and would achieve potential velocities, potential ranges and potential damage capacities beyond what there is in Rifts... not to mention the wear and tear the poor rails would have from accelerating rounds to speeds of miles per second.

Under "Other Weapons and Equipment" in the RMB, is a section marked "Rail Guns", it says the rail guns (the Rifts version, anyways) are "an electromagnetic system mass driver". (that is, not an actual rail gun, but more like a "mass driver" or gauss/coil gun)

IIRC, damage from rounds could be made nasty just by using lighter rounds at much higher speeds. (Force = Mass x Acceleration, or something like that)
I could be possible to make a small 9mm round (the standard "soft" type, no FMJ or anything) could do damage on par with 12.7mm ramjet rounds.

On the subject of the Boom Guns slug casing being a bit to long... If someone were to do something crazy, like increase the slug load by 50% (using up 2 of those leftover inches of casing length), you could get an effective damage or something like 4D6x10+30 MD from 300 slugs. (which would make it able to instant kill even tougher things, like a normal SAMAS or a heavy duty full conversion borg)

On a side note, this whole rail gun issue shows how "big guns" in rifts are insanely [/i]underpowered[/i] (e.g., a Boom Gun firing 3 pounds worth of slugs going mach 5 and doing 3D6x10 MD, but a 2 ton cannon firing a 15 pound AP round going mach 5 only does 2D4x10 MD...)

[Nekira Sudacne]

Rail Gun is nothing more than a name.

he could have called it the Peacok pistol and it'd be the same weapon.

don't get so caught in in meaninless classifications. just use the thing. it rocks

[Dead Boy]

We are told time and again that the boom gun is a rail gun, but I believe there is enough evidence to support the theory that the boom gun is in fact a conventional propellant artillery piece. On page 221 of the rifts main book the illustration clearly shows a casing ejector. Rail guns do not have shell casings, the entire round is expelled from the weapon. The drawing also says that the shell is 7 inches long, however according to the text the projectiles themselves only make up 4 inches of the case length... The recoil is another topic of contention, rail guns do not have recoil... Another place to look is in Free Quebec on page 69 we see flames exiting the barrel of the boom gun, artistic lisence..perhaps or the artist believes as I do. Also on page 77 we see a triax glitter boy firing his boom gun which is ejecting a smoking shell casing?? It is my belief that the boom gun was intended to be a conventional propellant artillery piece and not a rail gun from the beginning but the artist has no say and his version of the weapon was changed without comming up with a suitable reason for said change.

I read this post last night and was about to reply in the negative... but then I got to thinking. I believe that in principle, you are right. Originally, when Kevin Long drew up the details of the Glitter Boy and its Boom Gun, I believe that most of the weapons of the game were ballistic weapons with chemical propellants (be it solid or liquid). This must have been back in the early planing/conceptial stage of Rifts back when it was stlill tenatively called "Boomers". Because though you are wrong about the recoil thing (for proof of that, watch any action movie with guns blazing and notice that though they go *bang* the have little to no recoil due to there being no bullets going down their barrels), you do have a valid point about the shell's design.

As further proof that Rifts was originally going to be a bullet based game and not one of lasers and particle beams, take a look at the original weapons for the CS on pg. 203 of the RMB. The C-14 especially looks like it was designed to fire bullets and not lasers. I mean the thing has an obvious, ejection port, a groove for a side-mounted charging handle, and an exposed reciever!

So though things have changed in favor of directed energy and EM projectile weapons, it's plain as day that in its earlier concept phases, its tech level was much lower than what it is today.

Glitterboy

You raise a point that I find highly interesting : you make a distinct difference between a gauss rifle and a rail gun.
Call me a scientific/military ignorant, I always thought rail gun was just a synonym for gauss rifle... and am not sure where the basic difference lies between a system powered by coils and one that relies on a rail.. Would you have info on this subject, or know where I could find it?

It's simple really. Rail guns use two (or possibly more) rails that rund down the length of the barrel of the weapon. In the chamber is a bullet of sorts made from a conductive material, usually steel or tungston. A spark of electricity is sent down the rails creating an arc that grabs the round and drags it down the barrel at a fantastic speed. The arc goes nearly the speed of light, but the bullet doesn't (which is where they got the stupid idea of near-light bullets in that movie Eraser). The result is a Mach 5 bullet that hits really hard.

Gauss Guns use a different and more efficient system, which it is the more likely one to be used in Rifts. The entire length of the barrel is massive. Maybe an inch or two in diameter! Running through this is a tubular recipocating magnetic field, revolving forward on the inside and back on the outside. The bullet fired through a Gauss Gun never makes contact with the walls of the barrel. Instead it rests on, and travels through the EM field which expells the slug at fantastic speeds. Beyond being more advanced and having a higher cool-factor to it, the reason why it's more likely that this is the operating system of rail guns in Rifts (making them about as much of an EM gun with rails in it as the C-12 Laser Rifle is a "rifle" complete with a rifled barrel - it's just a name-holdover) is because with a Gauss system it's possible to fire bursts.

[Nekira Sudacne]

Here's another fact to swallow in support of Deadboys theory: The motorcycles in the RMB have an optional MD "Machine Gun".

so do borgs, rather than a Particle, ion, or laser blaster

[Vrykolas2k]

Hmmm... food for thought all round, but I agree that the Boom Gun is a gauss rifle.
And I'm glad the name of the game isn't "Boomers" lol.

[BigLEE]

Uh, the real world rail guns being tested by the navy have considerable recoil. It is less that chemically propelled weapons, but given the high acceleration of the round, it is still considerable.

[BigLEE]

Do you have a source of information I would like to look into that. All of the research I have seen has produced no measureable recoil, including military tests on tank mounted rail guns. The only concern with the tank mounted rail gun was power supply or a lack there of. I am always looking for new research.

Page 16 of the report at http://www.dtic.mil/ndia/2003gun/ellis.pdf. That railgun produced 63MJ of recoil.

I've also seen another Navy report, but I can't track it down a the moment, which also raised concerns about the effects of the railguns recoil on the ship's superstructure.

And you're maglev train example is really terrible. The passengers are just along for the ride.

[R Ditto]

While the whole thing of recoil of rail guns is interesting in that it's going out either side, it is the electromagnetic mass driver system that is the type in Rifts.
While true rail guns are interesting, it seems like they would be impractical for anything other than single shot weapons. Using ones that burst fires rounds would be not to bright IMHO because of all of the friction and wear and tear on the rails. It won't be to good if in the middle of battle, the weapon ceases functioning half way through its large magazine payload because the rails got wore down to much for the weapon to work right.

With single shot rail gun weapons, at least the rails have a chance to cool a little between shots. With the burst firing types, it seems the mixture of many rounds, friction and overall forces applied to the rails in such a short amount of time would cause the rails to be wore out much faster, if not cause other problems. If the materials of the rails expanded due to rapid generation of heat from friction, it could cause more friction between rounds/rails, and possibly speeding up the physical wear on the rails even more.

With the basic description in the RMB (of Rifts' Rail Guns being EM mass driver systems instead of actual "rail" guns), it at least shows that the average borg or PA pilot isn't going to need to worry about their rail gun conking out due to rail damage from excessive use. That and you don't need to worry about strange things like the sides of a gun exploding outward because the weapons structural integrity got damaged or compromised during a battle.