I would say you definitely displayed what you were trying to achieve here greatly. There is no question about what you were trying to do at all.
As far as originality goes, I'd say it is pretty original you do not see this type of thing very often, but the gun may be too close to it's reference in similarity.
You're technique is great but I must say more contrast of lights and shadow would be helpful with the depth. Also the fingers do look somewhat odd, the pinky fingers anyway. The other fingers are fine. Simply shade a bit harder next time, and put some slightly more harsh highlights.
Overall this piece is exceptional, the depth is the only real flaw here. If you were to do as I said earlier, and maybe get a little more contrast in this, it would work better.