Like I said I wasn't really sure.... he told me it was not advisable because the .22LR's were a smaller diameter. Leading is obvious, rimfires are dirty no matter what. He told me the best route was to build a dedicated .22LR upper, or buy a S&W Mp-22.... another one of my co-workers has the SW and we have shot thousands and thousands and thousands of rounds through it.... fun little gun.
Keep in mind this is a gunsmith I work with... he was not trying to talk me into buying anything, because he knows I would just build it myself, or order it on a prostaff form.
