Rail Guns

[Jschmus]

I was offline for a couple of days (computer crashed, again), so I don't know if anyone posted about this already.  I did a quick topic search and didn't find anything.  Anyway, the Naval Surface Warfare Center in Dhalgren, VA, conducted a test last week of a prototype rail gun.

http://www.news.com/8301-10784_3-9863174-7.html?part=rss&subj=news&tag=2547-1_3-0-20

[Supertom]

Wait, if the railgun uses no propellents or explosives, why is there a huge explosion when it was fired and when it hit its target?

Regardless...I want one.

[Rafael]

This particular shot attained 10MJ (MegaJoules), while a 5 inch gun only does not more than 2MJ IIRC. The threshold, as far as two years back was 6-7 MJ, so this one is greatly a success.

The big plume of fire at the muzzle is a perfect storm of factors, imagine the incredible pressures, thermal energy and friction an object exiting a launch rail/tube at more than 7 Mach should produce.

For this gun, it is foreseen that kinetic energy alone will be the kill mechanism

Rafa

[Jschmus]

The rail gun is intended to be a kinetic-kill weapon.  The test apparatus fired a 7-ounce projectile 80 meters in 20 micro-seconds.  Think about it.  I brought this up because it was all over the local news Friday and Saturday, and the NSWC is practically in my backyard.

[Rafael]

Not only kinetic-kill is envisioned. There's also been tests with explosive warheads, check this out:




All of them scaled down to 25mm for proof-of-concept. Problem is the intense heat and friction on the sabots and the stability of the explosive contents.

Rafa

[Rafael]

Jason, this is incredible!!
In your post at secretprojects.com the article you refer to (http://gizmodo.com/351467/navy-rail-gun-test-destroys-everything-it-touches-at-5640-mph) mentions that the shot was at 5640mph, roughly 7.6 mach. And at a third of its power!!

Obviously my info was outdated. They plan to reach 32 and then 64 MJ of energy!!!

Rafa

[Jschmus]

There was a teeny typo in my last post.  The test projectile weighed 7 pounds, not ounces.  The target was mounted on the side of a railcar, which was filled with sand.  The surface target was destroyed, and the projectile dug a huge divot into the sand inside.  The kinetic energy blasted aluminum fragments off of the opposite side of the container.  Just think, that was at a fraction of the projected power output.

[Jeffry Fontaine]

This link provides some very interesting images (http://www.powerlabs.org/index.html) for Rail Guns as well as what can happen when you introduce extremely high voltage to a normal produce section watermelon. 

Everything you ever wanted to know about how to build your own rail gun and from what this guy has done, it looks like you could visit Radio Shack and Home Depot for all of the materials you need. 

[cthulhu77]

Just got done working on some rail gun tech last week, this is fascinating!  Thanks!