Yo dawg, we heard you like poleaxes and guns so we made you a poleaxe and a gun in one package. You supply the axe/halberd head...
Some Japanese Tanageshima matchlock arquebuses from the 1400-1600s were up to 6 feet in length. This reminded me of some of the Hideyoshi era arquebuses. They had to be fired from forked rests and were employed in defending fortresses and ships because of how stable and easy to steady and aim once balanced on the rest.