A sci-fi blaster. The grip attachment is compatible with AR-15 pistol grips. 

The main body can be replaced with an air mattress pump. View the attached photos for markings and labels of the air pump I used for my build.

Print directions:

• Most parts can be printed 3 perimeters, without supports or infill if desired.
• Print the Body and Bits with infill to support the top surface.
• Do not print the clamp with many perimeters or high infill as it must flex.
• Print the pins 0.1-0.2mm smaller if you have fit issues.

Assembly directions:

• Place the clamp around the body with the cutouts aligned.
• Thread a zip tie through the holes at the open end of the clamp. Tighten the zip tie until the pump is secure.
• Place the retention arm into its socket with the top vent of the body inside the ring of the retention arm.
• Press or gently hammer the retention arm pin to attach the arm to the clamp.
• Install the grip with either an AR-15 grip screw or the printed rectangular pin.
• Use 2x M3x8mm screw to attach the barrel to the body.