I like M1A's. Not saying I wouldn't like an AR10, but my M1A has been real accurate so far.
Do you have a mount for your M1A yet? If not, I'd get a super low one, like an ARMS, and then just mount it with the TA51 mount. Yes, it will be kind of high, but it's not like it's horrible. I can still shoot pretty good groups with mine. I have a Springy Gen III mount with some low rings. But even though the mount is high, my scope is barely clearing the irons. So if your optic is going to hang that far back, which it might have to, to get proper eye relief you need to clear the rear sight, or take it off. My guess is the ARMS mount with the ACOG would be just about perfect.
Can we get a pic of yours? What kind do you have???????
This was a couple of weeks ago:
168 grain Federal ,forgot to put that in the notes
that's actually 6 rounds. But just 50 yards.