I just got my 22 lr rifle barrel from Mike at MbmCo. This is the one without a rimfire adapter. It looks fantastic, quality is everywhere. The muzzle has what looks like a perfect crown, welding, extractor are all great. The neat thing is the chamber, it is not cut with a reamer at all. Hard to explain but the bullet is pushed into an area(when chambering a round) before the lands and grooves that swages the bullet to bore diameter or something like that which eases the entry to the lands. It looks like that Mike uses a slightly taller lug which sets the bore a little higher, the case is struck on the lower rim. I'll post pic's soon.
Steve E........