i used to have a backpacker. Modded it by adding a aftermarket steel crosman breech and bolt and an 18inch recrowned barrel from. A nice chap from texas ordered me the parts and did the recrowing and i paid for the parts and postage to him and to the UK. Still worked out at about £35 for the barrel, breech, bolt, and a break he kindly chucked in free of charge.
Wish i hadnt of sold it so im currently modding my 1377 into a rifle. Ive got a crooked barn breech and extended bolt, camo pumparm and stock and now i'm looking for a barrel band and and a longer .177 barrel. Then i'll probably add a tr robb silencer adaptor and a silencer.
thats my plan anyway.
Danny
My collection = Ratworks BSA Scorpion T-10 .177, HW100KS .177 (tweaked by me), PP750, Crosman 1322 and 1377