I have done about a half dozen H&R's to 32-20, use a surplus british 303 barrel, I've also made them up in 32H&R mag, no problems at all. I really don't line them, just cut off the breach end and mount the barrel. Go to the H&R page and look up "stubbing". I have a Rossi youth 410 barrel I made up in .22 Hornet. Larry