It's a good question and I'm glad you all asked. Simply, yes, but not much. It is yet another known component once the gun is up to speed. It's not the distance the barrel rotates whilst the projectile is in it (barrel length is not a factor) it's the tangential speed of the barrel as the round leaves the muzzle. RPS x pi x 2 x r. A couple of m/s, maybe, compared to a muzzle velocity of some 1,000 m/s. That's my guess.