…or any CGI for that matter.
Very nice for your first project! My first stuff never looked this good!
wow. for a first project this is very impressive i must say. i can see some areas that can use some work but at this stage it wont do you any good for me to jump into technicals. at this point its just a matter of experience. good work. 
I feel bad now, haha! Awesome job for a first project. I hope I can do this soon.
Like everyone else has said, this is a great first model and Blender project. I think my first model was a gun as well, didn’t turn out nearly as nice as yours, lol
One thing I might suggest is using less sides on your cylinders, specifically the upper and lower barrel. I may be wrong but from what I can see you have the default amount of sides(32) on your cylinders. This isn’t really an issue if your trying to create a simple gun model like yours, but once you get into adding the subdivision surface modifier, it will create more geometry than you want to have and slow down your render times. A good number of sides to start with a cylinder that will have subdivision is 10, 12, or 16. Anything higher is just overkill.
If might also help to add a little AO(Ambient Occlusion), this will reduce the harshness of the shadows on your floor plane as well as make the edges of the gun look less harsh.
Anyway I hope you don’t feel like I’m critiquing you too hard, I just know how important it is to have good habits early on when it comes to modeling, or anything for that matter. Nice job on the model once again, you’ve got a great start
amazing work. i’d say that coming along great first project or 100th1