For the grenades I see
two options. I prefer the first but either one is good.
Going back to the suggestions, the first one is sleek in design. Very cylindrical.
I like them, gonna use the shotgun for the Spas-12 perhaps, as for the grenade, seeing as how it is a custom model it will defiantly will be used.
Just a idea, but can you make the scope see through for the ironsight? (Although no zoom be incorporated it would be like just looking through glass)
Considered, if it isn't see through I can put a transparent material over it, though I have no idea how to correct the actual iron sights. Keep these suggestions coming guys, I like what I am seeing.