The bazooka design is like a backwards coaxial.
The piston moves to the rear of the chamber when the QEV is open (triggered by blowgun), and the air rushes from behind, around, and over the piston.
I shoot direct fire, flat trajectory tennis balls at buildings and vehicles. Not a toy. Death can occur from a shot to the head from under 25 feet.
Chamber internal 2" pipe.
Front inside view of the piston/chamber when open.
Chamber with outside tubing just before welding.
Before front barrel welded on, piston closed/charged.
When pilot is vented by QEV, the piston opens and moves back, dumping the air in the chamber.

(The piston is not installed in this photo, just trying to give a visual of what happens.)
This chamber is setup is designed for an M9 bazooka (WIP).
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