Monday, January 14, 2008

Coil/Rail/Gauss Guns

In a note recently, J.D. brought up something about how small arms technology hadn't changed much in a long time, and it reminded me that I had I posted something on coilguns a while back. I haven't been keeping up on it, but I kinda like the way Donnie's coil-pistol looks and shoots. (Go to his page, and click on the four-target demo vid at the bottom.)

This technology still has some drawbacks. Projectiles need to be ferrous, and you don't want to shoot it next to anything that magnets will screw up. The rounds require more juice than you can stuff into a handgun to kick them out fast enough to be any kind of potent. The recharge times tend to be slow to get the capacitors up to snuff, but with better batteries, these things show some promise down the line.

Nothing useful in commercial production, and I suspect it'll be a while, but it's another interesting direction.


J.D. Ray said...

This looks about the size of a Desert Eagle (he may have been "shooting" for that), and not any more unwieldy than an Uzi, though obviously with a lot less magazine capacity.

I'm surprised, though, that he's using what amounts to a .308 bullet. Mind you, I wouldn't want to get hit with a 165 grain bullet doing 145 fps, even if that is slow in comparison to powder-charged rounds. Still, I'd think that, given his power density limitation, reducing the mass of the round would increase its speed sufficiently to make for useful ballistic parameters.

Also, if he's having this much success with a large pistol form factor, imagine what he could achieve with a bullpup design somewhat akin to the "blasters" the stormtroopers carried in Star Wars.

I suspect coil guns rely somewhat on barrel length to give a longer acceleration path, and a 24" weapon could reasonably provide a 20" barrel in front of the receiver, probably double what he has there. Extra battery volume, combined with better battery technology that's been developed in the last couple of years, and he may be on to something.

Steve Perry said...

Go on YouTube and check out some of the bench-mounted bigger guns. There's one that shoots a steel rod pretty hard. I think the velocity is a measure of juice and length, but I think projectile density figures into it. A rifle could probably be made now that would launch a small projectile at fair speed. But it's not efficient enough to make gunpowder or air or gas guns nervous.

There are pre-charged repeating air rifles that will shoot a 9mm round hard enough to knock a deer over look at the ShinSung --

I've got a pump air rifle that will put a .177 pellet or BB out at 1000 ft/sec. There are others that will zip past hypersonic, no problem. Gamo makes a break-barrel for about $150 that claims 1600 ft/sec.

Be a while before rail or coil guns get that effective, I'd think.