This is my airsoft howitzer inspired by Kittka's Rapidfire airsoft cannon. Lay siege to your desk with this mini howitzer. Fire multiple airsoft rounds at once. 4 pellets at a time works great.

Howitzer cannons have been on the battle field since the 17th century. The in between of a gun and mortar, howitzers have often been used to lob ordnance into advancing enemy troops much the way long bowmen did in their day.

"A howitzer is a type of artillery piece characterized by a relatively short barrel and the use of comparatively small propellant charges to propel projectiles at relatively high trajectories, with a steep angle of descent." -Wikipedia

designed to use #6-32 screws everywhere but the joint of the trigger and firing pin. That is for a #4-40. Clean the bore and loading gate with a 1/4" drill bit. I printed without support material but had to do a bit of clean up.
If your printer is good at bridging go without support, other wise print the tilt slide with support everywhere and the rest of the part without support. I used a .2 mm layer hight.