The question asked:

I was reading this article about railguns, coilguns and some of the technical problems involved and it mentioned that (theoretically) an operational rail gun could fire a projectile 250 miles in about 6 minutes. If you really could fire a projectile this fast and this far how hot would it be when it reached it’s target.

Assume the projectile is made of tungsten and is the size and shape of a 12 oz can of soda. At that speed and considering atmospheric resistance how hot would it be when it got to the target?

The answer given:

If I haven’t missed something in my math, this comes out to be 2,500 miles per hour which equals about 3,600 feet per second. You most definitely could–and a lot of off the shelf rifles do–fire a projectile (bullet) this fast. The projectiles are much smaller and lighter than the one you propose, of course, around 50-150 grains in weight.

I keep thinking I must have bothed the equation, my result is not a very amazing speed. (250 miles in 6 min = 2500 miles per hour [which divided by 3600 secs in an hour]= .69444… miles per second which times 5280 feet per mile = 3666 feet per second)

No idea about the actual answer to your question, though. I know the SR-71 at speed (~ Mach 3 or so), did get its exterior skin very hot, but I don’t know just how hot, sorry.

What is the answer? Wiill we ever know?

(via the straight dope)