What kind of gun is that and what is the doohickie under the barrel?
And how many rounds?
Ah - to the best of my knowledge, that’s a Glock 17 (in 9mm) with a 30-round magazine. The doohickey is a combination laser sight and flashlight. I’d guess the weight of the ammo in the mag might offset the weight of the hardware on the rail. Only guessing.