I was attended to this upload, and i loved it.
I found the bullets a little small. so i gave it a try.
Remodeled the alien bullet. And made a case for the gun.
The gun is the original upload from ScottyJMMcKay https://www.thingiverse.com/thing:2985872 , just combined it with the case.
ScottyJMMcKay, thanks for your design