I've got a 222,6x47 and 6mmrem all single shot plus have some custom rifles
build on the 40x action. I don't know about now but when I got my 40x's the factory send a test target with two 5 shot groups with bullet and powder used. You can call Rem custom shop and they may give you the load they used for testing and I'd say when that rifle left the factory the test size groups were about 1/2" or less. I had a 40x repeater 308 with a slot for the stripper clip and the groups were in the 1/2" range. I've had real good luck with the 40x and since most of mine were new I never changed anything till I need a new barrel in fact had the custom shop rebarrel one 40x for me and it shot as good as the orginal one. I think you have a pretty nice rifle. I've got an older rem 700 in 7mm express (280)and it's still a good shooter. Well good luck.