"The Cannon" an under slung blunderbuss nerf blaster

The version of this that I made uses a PVC pipe for the tube, but the printed one should work fine. I recommend at least 3 walls, and 35 to 50 percent infill, on the picatinny connector I used variable infill with the bottom half being 50 percent and the connector part at 100 percent infill.

The file “Bar with Picatinny” is optional for if you want to connect it to a blaster, and it is attached the same way as the rest of the bars but it uses 4-40 screws to secure itself on a picatinny rail. It should be printed using supports, and if you feel like remixing it I heavily encourage it because it wasn't very elegant and could be done better.

All of the files excluding the one mentioned above print without supports.

The part “Trigger pin” didn't want to work for me so I used a long screw to hold the trigger in place, anything that fits through the hole on the piece “Tube rear support” should work to hold the trigger.

This blaster requires 9 m3 by 10 screws, some form of elastic or rubber band (I used old hair ties), and a spring with a length of about 125mm and an internal diameter of 21mm/ outer diameter of 25mm (I took one from an Xshot Longshot), lastly an optional 2-4 4-40 screws for attaching the cannon to another blaster.

Assembly

fit the piece “Front stop” on to the tube, then put the piece “Tube rear support” on to the other end of the tube. place 3 of the bars and thread m3 screws into all the holes, the bars have cutouts for the nubs on the front stop and rear support, which should be attached with the 3rd cutout behind the rear support. Put the plunger face in the tube from the back, and then place the spring in the hole of the plunger face. Then put the spring seat into place with the 3 cutouts on the bars, and place the spring into the rest. On the rear support there is a spot for the trigger/catch place the trigger with the holes aligned and put the trigger pin or a similar object in the aligned holes. Place a rubber band in front of the catch in a way that it holds the catch to the tube and loop the other end around one or multiple of the bars. If you move the plunger all the way back and it catches you are done, congrats!

How to use

Move the plunger until it catches at the back of the tube, load darts into the tube, the hit the lever on the catch and it will empty the tube's contents into the general direction of where it is being pointed. Have fun!

Side note

If the plunger sticks all the way forward and you can't prime it give the plunger face a good smack with something like the bottom of a mag, a blaster grip, a stick, or a mallet and that should get it working.