Pretty good although it is not an exact model and is a bit square... if you are using 3ds max or maya or some other professional modeling program, try using smooth shaders to make it look more circular.
BTW: 900 polys for a main weapon too much? lol I would reccomend atleast 1500 polys for something that you see 24/7 in your game. (This is why first person shooters have 2 models per gun, one very high poly (10,000+ sometimes.) for FPS view and one (1000+) for enemies.)
