This is the P304 REVERSS. It has an unique rotary barrel.

Like a helicopter.

Muzzle notch and holding hook.

Rubber band is pushed up by the scorpioid releaser.

Before shooting.

After the 1st band is released, the barrel begins to rotate.

It does a one-eighty. and 2nd band comes at releasing position.

Ratation by a rubber band power.

Trigger spring inside the grip.

The 1st design.

With the 1st trial work.

Urethane paint finished.

Please watch the video.

YouTube video