Thanks guys. I figured at the time that pushing any overpair 77+ was good but I just wanted to make sure. It was a weird situation where betting the flop with 77 would probably be bad because I'm behind MP2's range, but once there's a call and a raise, shoving 77 is good as a bluff vs. MP2 and for value vs. CO.

Anyway I shoved 99, MP2 folded and I held up vs. A4o