The old US standard for the 28ga was I believe 2". This converts to 63.5mm, a 65mm shell is 2 9/16". When I began shooting way back in the 1950s the standard US length for 28ga had become 2 7/8", I'm not sure just when that length was dropped to the present standard of 2 3/4".


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