English are good for talks.
I'm not sure why the OP is asking this, since the whole principle of a railgun is that it wouldn't kick back. Given how horribly energy-inefficient such a weapon would be, I don't see why anybody would want to make one. Go learn some wikipedia physics if you haven't already.
QUOTE(Kaosumx @ Mar 2 2012, 01:48)

Pretty sure it doesn't have recoil because the way it applies force to the projectile is different. Guns use the expansion of gas in order to propel the bullet, which pushes back and causes recoil. A railgun's rail instead are getting pushed apart instead of backwards.
That is kind of a concern though, isn't it? If the rails push apart, couldn't the thing just rip itself to pieces if the force is sustained for long enough?