An interesting picture, Pip. Don't feel the need to change it just because other people say they don't like it.
Having said that...
*I*, if I were to have designed this gun, would have located the ammo counter on the back of the stock so that the operator can face it without having to flip the weapon (I understand that it's a 2D picture so that would be sorta difficult). Also, I'd place the magazine either side-feeding or top-feeding just because the magazine sticking out of the handgrip would make firing from a prone position difficult. And, I'd reposition whatever that metal rod is on the back (don't know if you intended this to be a bipod or a folding shoulder-stock) to the front to support the weight of multiple barrels.
But, hey, this is just nit-pickiness on gun mechanics, not on the artists' ability. Don't change anything on our accounts.
Snazzy logo, too. PipBoy Productions.