The future of firearms?

[ABNinfantryman]

imported post

I'm pretty sure the Navy just successfully tested a railgun, granted it's massive and more for naval bombardment than personal defense, if they could scale it down it would make for one effective PDW. Bigger roundsor more round capacity since you would no longer need a case of powder to take up space.

http://gizmodo.com/351467/navy-rail-gun-test-destroys-everything-it-touches-at-5640-mph

 

[tekshogun]

imported post

Weren't the "special guns" in the movie Eraser, railguns?

 

[The Atomic Ass]

imported post

ixtow wrote:

You're missing the point. It isn't a weapon. You can throw rocks and do dozens of times more damage. 11J? Google and a Calculator (or just google, it'll do math and unit conversions if you type it in the search line). Take a look at the efficiency number, and run that backwards for flux density and current in the coil, temporal duration, etc.... Even 'throwing rocks' is so many orders of magnitude greater, it makes a bad comparison. If you spit really hard, maybe?

Well, I think the energy could be comparable to a weaker handgun, say .380 ACP, but we'll see if my math can hold up.

This is just my Google and calculator inspired math:

The article lists 45 gram projectiles, which according to Google is just a hair under 650 grains. Now IIRC, that is up in .50 BMG territory for projectile weight. So reducing the projectile weight would result in a much increased velocity. How much more, is what I don't know how to calculate.

The article lists two different velocities, 85 KMH, and 110 KMH. These work out to 77 FPS and 100 FPS, respectively. Roughly one-twelfth to one-tenth of a typical handgun cartridge, for a projectile that is in serious rifle territory. I wonder what velocities can be had out of 55 grain .223?

I'm going to assume his charging resistor (light bulb) is 100W. With a rated charge time of 8 seconds on a mains connection, that is 800 watt seconds, not considering current drop on the end of the charge. I can foresee designs with 4lb battery packs that do not require capacitors.

 

[Grapeshot]

imported post

velocuty of bb gun
The Atomic Ass wrote:

snip....
The article lists two different velocities, 85 KMH, and 110 KMH. These work out to 77 FPS and 100 FPS, respectively. Roughly one-twelfth to one-tenth of a typical handgun cartridge, for a projectile that is in serious rifle territory. I wonder what velocities can be had out of 55 grain .223

I don't think so. The velocity of a cheap BB gun is 400 - 600 fps.

Yata hey

 

[ixtow]

imported post

Grapeshot wrote:

velocuty of bb gun
The Atomic Ass wrote:

snip....
The article lists two different velocities, 85 KMH, and 110 KMH. These work out to 77 FPS and 100 FPS, respectively. Roughly one-twelfth to one-tenth of a typical handgun cartridge, for a projectile that is in serious rifle territory. I wonder what velocities can be had out of 55 grain .223

I don't think so. The velocity of a cheap BB gun is 400 - 600 fps.

Yata hey

The man did the math himself, and listed the Joules and efficiency.

My son's old BB gun could push 700fps. Just shy of supersonic.

Energy = Mass * Velocity. What's a Joule ( = E )? Figure out how many Joules a .22lr is, and you'll start to understand.