>>525480
The gun is just a platform for the ammunition. Sure, you can make one that can eat different kind of foods, but you have to either design the weapon for a few existing cartridges, and develop some new ones that are compatible with the weapon, or design both new guns and new ammo.
>>525542
>make gigantic nuclear-powered atmospheric cruiser
>armour it up like a battleship
>put hundreds of tons of various ordnance on it
>let it rip
I'm positively sure it would have been cheaper than the F-35.