No real input, but.......
From what I understand the 770 is the junk predecessor to the 710 (which I own, also junk). I've been told I'm lucky I got one that shoots straight. Mine was rendered a single shot because the mag release won't properly seat into the stock now and the mag won't hold I'm the mag well anymore, they make zero parts for the 710. This has made me grow a strong hate for Remington and taught me a valuable lesson, but I was 20 and needed a deer rifle and didn't have much cash at the time....
if you don't figure somthing out let me know and I'll give a buddy of mine a shout