No, I mean like. You could take the cannon apart so it's a bunch of derringers and find a way to make sure the derringers form a cannon really fast if you needed something more powerful. Have the derringers use some other form of energy to combine into an attack with extreme damage.

[It sounds like a decent idea in his head but so did the team attack name flower power and no one liked that.]

And the 4-tier gun could either form into one, or be taken apart like those others guns you mentioned. So you could dual-wield if you needed to.