One of the steps in modifying an A5 for 2 3/4" shells is the removal of 3/8" of wood from the front inside of the foreend. This exposes part of the non blued portion of the barrel extension in front of the receiver. It is part of the lengthening of the "stroke" from 2 9/16" to 2 3/4".
The ejection port is also lengthened 3/8" by removing metal from the front edge. Those are just two of the steps, but you get the idea.
Another obvious thing to look for is the ejector claw on the barrel extension. If it is short and fixed in place it is for 65mm chambers, if it is mounted in a sliding rivet and can extend back past the end of the barrel extension 3/8" then it is for 70mm chambers.
2-piper, what your describing the normal set up for light shells, I'm not sure of another set up for light shells....
Bill, cutting down the friction ring is a neat trick, I've never tried it. I have a very old spring that I use, it's lost enough of its "boing" to handle lighter loads pretty well.
Jeff
