My Sauer was indeed stamped 2 3/4" on the face of the ejectors. Happenstance or not, if a 20 is in fact a 19 (as marked on BOTH flats of that gun), then it's overbored for a 20. Standard BD for a 20 is .615; for a 19, .626. If one doesn't pay attention to those proofmarks when measuring BD, one is likely to think someone's done some serious honing--when that's the way it left the factory.