Gunman;
I Quote me;
Quote:
That may well be right if you deal only with good quality British built guns.

I did not you see totally disagree with you. I did however you see spend 35 years in the machinist trade & am familar with precision measurements. What we are measuring in determining chamber depth is the junction line of two cones having different angles to their respective walls. An exact measurement of this junction with a solid plug gage requires an exact match of plug diameter to junction diameter.
Since this is a "World Wide" forum I just wanted to make certain that others out there realized that while this plug made to British Specs might well give the desired results on the Greener in question, it is certainly "NOT" the "ONLY" way of determining that length. If someone should try to apply it to guns of other nationalities it may in fact not even be a reliable method.
Nuff Said; If you don't understand the basis of measuring chamber depth, then that's your problem, not mine.

Miller/TN
I Didn't Say Everything I Said, Yogi Berra