This is Escape Velocity from Destiny for all you spray and prey dudes :-)
Pretty straightforward print and assembly, just make sure the barrel separator is kept in two halves then use it to clamp the upper barrel in place when gluing.
Looks ok without the sight if you don't want the hassle of printing it and the screw heads are optional for those that want more detail. I printed these on a raft and with a brim, painted them the whole assembly in one then separated each part off.
Probably not a good choice for Cosplay as it looks a lot like a real submachine gun so good luck at weapon check ;-)
P.S. Check out my facebook page Bigbangcollectables for more cool models