[ArrogantBustard]

a 3/8” will work for a 9mm (tight, .375 vs .380)

9mm = .355", .38SPL = .357"

[MrB]

Is that bullet size or brass OD size?

[marktwain]

a 3/8” will work for a 9mm (tight, .375 vs .380)

9mm = .355”, .38SPL = .357”

Simply a difference in chamber vs. bore diameter. ;-)

Chamber is about .380, Bore is .355 - .358. Trifling differences for homemade.

I think steel tubing exists in enough quantities, and is easily modified in inside diameter, to offer a variety of sources for .22 barrel liner material. It is not even that hard to make rifling, though it would take much more time than printing the gun.

Lots of tubing out there that could be made to work.

http://www.microgroup.com/Products/StockTubing/fractional_tubing.asp