I've got that same M77 .458 and it's surprisingly pleasant to shoot - just a good shove, not abusive or painful in the least, even off the bench.

I plan on replacing that rear sight with an express leaf type and may or may not look into the conversion to CRF. As it is now it's a very slick action. It's been 100% reliable and shoots like a dream, so can't say much bad about it at all! I even like the tang-safety as it's very fast and natural to get into action.