Railgun varient

  • Last Post 25 July 2018
Nightstalker666 posted this 14 July 2018

I have a great idea but it involves all the experimental stuff I've heard and read about IRL as well as other SCI-FI and BT itself. first off gauss is a very unstable and inefficient way to use electricity to launch a projectile and takes extra work to sync up each coil. a railgun needs a tougher barrel to keep from splitting itself apart but has no need for moving parts nor in particular for a special timing/syncing system to work properly. you just run the charge on each side of the barrel and the opposing charge pushes magnetically inclined projectiles out. 

now caseless and pulse technology; not pulse-lasers but the idea of igniting the propellant from all sides at once via electric charge. from what I've read about caseless munitions that would be an ideal combination instead of adding a mildly volatile primer cap. also pulse ignition is vastly more efficient and is being experimented (IRL) on for jet propulsion as well (the aurora project, supposedly. other more official public research is being seen nowadays too though, again IRL) 

now I want to talk about custom munition. think of a projectile shaped like the so-called aurora of one of the SCRAAM-jet concepts. build something that looks like that with a special blend of hardened metals and a diamond point on the nose capping a hollow-core through the projectile that a pulse laser shoots through as the propellant gets zapped. this would superheat the core and the flightpath in front of the projectile possibly even softening up the target as well if within effective range which would probly be within minimum range. now back to the special blend of hardened alloy; using the type of machinery used to condense carbon into industrial diamonds to make the initial projectile -before coring it out and adding a diamond-point- as compact, rigid and hard as possible the design-team managed to figure a way to make it so that the metals in the heated core would ignite as a plasma rocket adding still more to this projectiles already extreme velocity. 


so with all that fluff I want to make all the specs for such a weapon and figured I'd put it on the board as a creative line of thought. I probly don't need to figure the pricing (just assume astronomical, and not for sale) but I'd like to try and figure how I should equate this into Tonnage and critspace, BV, and maybe get some idea's as to where I should place the range and damage values at. 

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Nightstalker666 posted this 14 July 2018

Taking the Gauss rifle as a similar base weapon to compare. 

1 heat, 15 damage, min2/short7/med15/long22/extreme30, 12 tons/6 crits, 8/ton ammo, 300k-c-bills +20k/ ton ammo @360BV(2.0) with one ton ammo(320 base BV) 


so I'm thinking around 3 heat, 25 damage plus AP crit effect, min6/short12/med25/long39/extreme50 , 10 tons / 4crits, 16/ton of ammo, 2.5M-C-Bills +400K/ ton of ammo, @around 7-800 BV seems appropriate but I'm not familiar with the BV system too well. grew up CBT with nothing newer than 3025 and there was no BV back then.

Prince posted this 14 July 2018

Yowza those stats. Even at 800BV a piece that's OP as hell.

One thing that bears discussion is that gauss rifles in battletech are coilguns due to both ease of manufacture and due to maintenance. Railguns are a cool concept, but even the US military had problems with barrel warping- rails of THAT sheer magnetic force sitting next to each other, whipping a projectile out at tiny C-fraction speeds did work, but required an insane amount of power and destroyed the barrels after (I think) 3-4 uses. But when you're charging up a solid piece of Iron with mejajoules of energy, what do you expect?

Now BT is sifi, but it likes to be "hard" sifi and I personally think the weapon should represent it. Straight away, firing the gun might kill the thing- the barrel's warp heavily and the capacitors could power a city. Multiple torso locations would be needed- like the HGR- ammo is in 3 rounds/ton, and it's primary use was likely destroying fortifications and walls instead of battlefield units. Finally, like the HGR it makes a 'mech unstable, but it also makes them far more likely to fall over when firing.

Thunder posted this 15 July 2018

BV would be 704, (88 for the ammo/ton), according to the Heavy Metal Custom weapon thing.


To be clear,  You're firing a projectile, and then shooting it with a laser to give it added acceleration?

I'm uncertain if you're going for magnetic acceleration or a electro-plasma pulse gun for the initial shot.

Nightstalker666 posted this 16 July 2018

Thankfully its sci-fi as you said so I can adlib without a physics PhD. I was thinking the magnetic acceleration would be fast enugh that the round would be out the barrel before the laser had managed to superheat the special core materials enough to ignite the plasma, also machined inlets around the diamond-tip into the core. multiple sources of acceleration that I haven't a real clue scientifically if they'd have any proper combining attributes. 

this would be one of those one of a kind things in the game a "unique" in many modern RPG's. so the fact that it's OPAF is supposed to be balanced by that and all the hassles that come with it. extreme maintenance cost from a specialty technician the MechTech would have to have on retainer or routine times. the surrounding storyline and battleplan to lay out to involve such a weapon would make the munchtek fun and have meaning. 


however I was hoping just looking at what kinda techno babble fluff I've construed behind this and what kind of stats would anyone else try to keep it from being a holy grail, I shouldn't want it to be too epic, not supposed to be alien tech or anything afterall. so plz any suggestion for how much to dumb that down without taking it's reason for being...

Thunder posted this 16 July 2018

Two paths.

A:  Hard Lasers.  Pulse laser hits the target, but micro particles are added to and propelled by the laser to add kinetic damage to the strike helping to defeat armor layers.   This feels like a reinvention of Re-engineered lasers.  But maybe with ammo constraints.  Or give them the re-engineered lasers anti armor abilities, and turn them into actual high impact cannons on the PPC scale of things.


B: Laser Cannons.  The middle ground between Auto-cannons and Gauss rifles,  high energy lasers provide propulsive power over old fashioned explosive rounds in a barrel.  The result is Gauss rifle like performance without the need for the heavy coils and capacitors of the traditional gauss rifle.  The cost is in higher heat build up.

In terms of tuning what you already have, I'd drop the range to LB-2x ranges.  And jump up the heat by a considerable margin, probably around 15 or so.

Nightstalker666 posted this 16 July 2018

off the top of my head I think that was 28 or 32?.. I gotta agree some heat to pay helps the balance all by itself but I think 12 is what I'll actually have it set to in mine. what do you think on weight and bulk?

Thunder posted this 16 July 2018

Clan LB2 long range was 30 IIRC

Its too light and small for what you're getting out of it.  If such a thing suddenly showed up as an available piece of equipment it would cause a massive change in the dynamics of combat unit design.

It would also break fluff.  Its an Idea of what is possible now,  and yet in the next 1000 years is never gets used.  Must be some reason for that.  (Unless you tie it in with some other bit of new technology that finally made this one possible.)

For the mass and space,  I would expect a weapon that can put out 10 to 20 damage at Medium range.  Examples are UAC-10, HAG30, Plasma Rifle.  For the damage and range you're after, 15 tons and large quantities of heat is about the minimum.

Nightstalker666 posted this 22 July 2018

I cant let this be mounted on fast movers, I'm gunna double the weight to a flat 20T/8 crits. Indirect-fire incapable so the range only really works from a bastion or mountaintop to make the range and power for nothing in the wrong hands. I've been toying with BattleTech 2018 and supped up the Highlander and gauss specs to run the game through and despite the massive boosts I've given myself in the game, tohit and LOF make it so my unboosted opponants still are taking 2 full barrages from assault mechs and only sometimes going down then, the heavys and rare assaults take 6-7 full devoted assault mechs AND a "Railgun" much like the one I'm talking about in this thread. if I weren't playing against AI everyone on the field would stay out of sight and LRM the hell out of me targeting my "gauss/Rail-gun" until I lost the weapon or conceded just to keep from having to pay the massive repair cost if I let it get bent even a little outta shape.. Basically this would be an assault mech defender of a base type weapon. as powerful as a longtom but direct fire only. and those 25 pts act as Armor Piercing and don't get divided into other locations even if blown through unless the next place damage could be slid to is directly behind what was disarmored and de-Internal-Structured such as from the front CT to the rear CT after all the I.S. and the two or three required crit rolls for such a catastrophic occurrence. 

Ammo crit does 2pts per round due to the safety features of the caseless munition: it HAS to be zapped or it only smolders and fizzles out so only PPC and Laser weapons can cause the full 25pts/rd, or at gamemasters discretion act of god lightningstrike crits the ammo (or since we ARE afterall talking of bring one OP unique prototype weapon to the field. a closer truer lightning than the PPC might have close-in indirect fire and metal-heavy targets give it a bonus tohit, this would be a great counter fluffwise, now I'm gunna have to think THAT out, haha!) .. overheating and flamers/infernos, etc. have no effect on this type of ammo. 

also thinking this as another possible mitigatory but it seems excessive: even with laser-like precision the targeting computer of a base mech cant handle this weapon. so a devoted Targeting computer that disallows the unit (short of a dropship whose computers do that all day) from having any other direct-fire weapons to keep from overloading the TC. 

I thank you all for giving me some commentary to chew on and feel free to continue the thought and I'll get back when I can..

Captain posted this 24 July 2018

(Hoping this works)

After seeing the MekTek version in Mechwarrior 4: Mercenaries, I'd come up with my own stats for such a weapon. Take a gander:

Heat: 5

Damage: 50

Range: 10/11/22/33

Ammo: 2/ton

Weight: 30 tons

Space: 22/NA/1/22/1/1/1/1/1/1

Special Rules:

A critical hit to the Railgun causes it to explode catastrophically, equivalent to a 60-point ammunition explosion.

If the 'Mech mounting a Railgun is not in the Super-Heavy weight class, its controlling player must make an immediate Piloting skill roll to stay standing at a +1 penalty for an Assault-class 'Mech and a +2 penalty for a Heavy-class 'Mech (Medium 'Mechs automatically fail the roll.). This penalty is doubled if the 'Mech moved this turn. Superheavy 'Mechs that move and fire the Railgun in the same turn make a PSR with no penalty.

As for cost and BV, I have no clue what they would be (other than "hella-high").

Nightstalker666 posted this 24 July 2018

helluva hunter-killer weapon if your the type to dig in and brace at a sniper position, but as with a sniper he'll HAVE to have close in support close by.

BT2018 you could make and test such a weapon. make it so that firing impacts your "stability" which is incredibly easy to find and modify (via text/word-pad!) as are all the other usual stats. I redid the LRM-20's to clan specs myself, but finally looked into nexus mods and "Roguetech" already made a full unofficial add-on with all that stuff and more. even if you cant play BT2018 on your PC (I barely can and I'm technically not even running min-spec req.'s) you can look that up and appreciate the work they did.

Nightstalker666 posted this 25 July 2018

I still want a hard-hitting accurate sniper weapon that's small enough to pack as a literal mech-sized rifle or even an OICW in mech size... think Barrett XM-109 resized for a mech now THAT would be an awesome sight. and a way to literally fit it with a clip. such a thing would take specialized hand actuators, an especially compact system behind as big a barrel as could be manageable to scale with a man... say a Stinger or Javalin launcher as an Arrow IV and each shot has to be breach-loaded or even sealed one-shot...

Captain posted this 25 July 2018

Unfortunately, that kind of dexterity is outside the realm of BattleMechs.