if your already pushing 3000 polys i wouldnt add anymore detail if i were you. i would concentrate on fixing whatever is wrong (like the guy said above). then id start optimizing it. if your serious about putting that model "in-game" then i can see alot of stuff already that u might consider deleting. with the blaster that i made (a few post down), i had 2400 polys. ive already got it down to 2100 and you would be hard pressed to even notice a difference. you prolly want to start on the front front of the gun, getting rid of the parts that are not facing the player. but if you just making it to learn techniques then just keep happily modeling away!
The model looks great. Not very difficult to see that you put a lot of work into it. Since I really don't have a reference brain myself I can't complain about anything. Good work!
Its not the most acurate weapon in the world and some of the angles seem very stiff.
The way you have actually modelled it seems alright, but from your fractal render you can tell you havn't put perfections to a lot of areas. In some ways you have wasted a lot of polgons and it seems to be rushed.
I would sujest going over your work and perfecting it, make sure its ready for Unwrapping and skinning and remember this will be in a mod (i think) you really need to spend time looking at your work and also the weapon you are modelling, if it doesn't look the same as the original or just look good in general continue to perfect it until it does.