For Christmas last year, I bought my grandson a 243 and an Athlon scope. He decided after using it, that he wanted a 4 power. That shocked me, but no problem. He was at the house, so we took his 3-12 and I put a Weaver fixed 4 on the 243.
I decided to put his 3-12 on my latest Encore barrel. It's a 26 inch, 7.62x54r straight contour from MGM. I ordered this about 7 months ago, and just got it.
I was worried that the scope wouldn't have enough fore and aft travel to get the proper eye relief. I am happy to report that it works just fine! It is a Game Reaper, one piece aluminum mount.