Is there any plan to produce these commercially, perhaps to begin with as a 'cottage industry', on an occasional basis? Where does the barrel come from?

One of the most interesting developments in air rifles - which almost needs a separate thread - was the Greener and I only thought of this yesterday when I saw one at Kempton. The lever to the side of the barrel closed the barrel onto the loading port, which protruded into the barrel when the lever was closed. This ensured efficiency of transfer between air and pellet but, presumably, the new modern seals have made this concept redundant.

Rgds
A