Sorry for the delay....
I had not intention of actually unsoldering the two, but an impromptu experiment of which is stronger, epoxy or solder (epoxy this time) left me with a partially removed barrel and bent breech/reciever. So in the interest of science and advancing the cause of airgunning, I finished what I started some time back and unsoldered the breech/barrel from the pump tube
Please note the barrel to breech connection, the short bit of tube soldered in, and how the breech is curved to fit "flush on the pump tube.
I'm also guessing that they may have used solder paste, instead of soldering it like a plumbing joint.
I'm thinking a riser plate(3/16 or 1/4) between the two... could still use Phil's idea of a 22xx barrel he described earlier. Or maybe just use the stock barrel, cut it down some to allow shroun internals.....A barrel band or two is definitely in order.
The only gotchas adding a riser plate that leap to my subzero addled brain is the change in cocking pin geometry and the added dead space that must be filled by the aircharge to drive the pel down the barrel. Another thing may be how adding the riser and a shroud will change sight/scope mounting options
dr_subsonic's pneumatic research lab
the Lunatic Fringe of American Airgunning
Southwest Montana's headquarters for Airgunning Supremecy