[dpvu]

The fuse is there to protect the gun. Just because it's "LiPo Ready" doesn't mean it can handle excessive current. The fuse could (and they do) blow using mini/large NiCd/NiMH batteries. It's just a matter of too much current being drawn. This usually happens when you hold down the trigger after the gun has locked up. The motor keeps drawing more current and thus the fuse blows.

You don't need to up the amps on your fuse. You risk melting wires etc. if you do that.