Mixing guns and...

[Aleolus]

Ok, so I just recently finished watching season 3 of RWBY, and I got to thinking: What are some fun and (reasonably) effective ways you could mix firearms with melee weapons in a D&D//Pathfinder setting? My idea, taking a page from the character in the show that uses a giant hammer, would be the same, but have the gun part be on the opposite side of the hammer head, triggered by the head hitting something. Then, the recoil of the gun adds extra force to the strike of the hammer!

[Âmesang]

Personally I'd stick with the gun-in-the-hilt option utilized by Cervantes de Leon in SoulCalibur.

[madtinker]

There was an expanded universe star wars novel that had blast swords - when you clanged your blade against something, it fired out of the end like a blaster. Rules wise, just say treat it like a "burst" weapon (shocking, flaming, etc), except that the damage is equivalent to a primitive (or not primitive) firearm.

[BWR]

Pathfinder (http://paizo.com/pathfinderRPG/prd/ultimateCombat/combat/firearms.html)has things like the warhammer-musket, pistol-dagger, axe-musket etc.

[mabriss lethe]

Eberron also had Spear- and War-spikards, which were exotic melee weapons, in the respective forms of a spear an a warhammer, that added crossbow bolt damage on a successful hit (with attendant potential for ammunition enhancement stacking shenanigans)