No, not if you used a normal pistol or rifle. There are a number of questions to consider here, firstly – would a gun fire on the moon without any oxygen to support combustion? Modern bullets have an oxidising agent in the explosives so they would fire in a vacuum. Secondly – would a bullet be pulled back by the gravity of the moon? The speed that a bullet leaves a modern day pistol or rifle is about 1 km/sec and the escape velocity of the moon is 2.38 km/sec so it would fall back to the surface even if fired vertically upwards. Thirdly – if a bullet could be fired at high enough velocity to escape the moons gravity would it enter the Earth unscathed? Not if it was a lead bullet, we think that with such a low melting point (327.5 degC) a lead bullet would melt due to heat produced on its way through Earth’s atmosphere.
