It's really inadequate for moose. Even 6.5g is light. I suggest 308.
I've seen moose taken with 5.56 77gr with a brain/cns shot but I don't recommend it. Intermediates are too small for game of this size. Please don't.
Yeah I’d not recommend anything less than a 308 for moose. 7.62x39 is pretty decent for whitetail/antelope but you still want to use a good hunting bullet, not wolf hollow point. The soft point 154 grain from silver bear is a decent round for brush and short range ie <250 yards.