Quote:
surprised that the proof marks didn't get struck off

Small matter, but this is not really a "Proof" mark, but a maker's mark or Logo.
A proof mark is an official mark applied by the proof house showing it has passed some form of proof test. This mark simply tells who made the bbl tubes.
Couple of unusual features often seen on guns of this era; Seems most guns from both earlier & later do not have the small upper pin to guide the extractor, but use the rib extension instead. Also many along this time frame have the hammer axles turned to a smaller dia at each end & protrude through the side plates. Have not looked at your pics yet, does it have this feature?

Last edited by 2-piper; 02/10/08 12:16 AM.
Miller/TN
I Didn't Say Everything I Said, Yogi Berra