Mag constraints seem to indicate I'll be about .085 back from the lands,

I'm assuming that's fairly normal.

Any other mags that somehow allow longer COAL?

Pmags is what I have on hand.

Just load them at 2.25" and forget it.
Bullets like the Sierra MK 80, Hornady 75 & 80 ELD and heavier bullets are meant for single-loading only in ARs.
The 77 Sierra TMK is about the best BC bullet you are going to find for mag-length shooting.

I do just like Tyrone does. I use a lot of 10 round P mags and have no problems with accuracy. KISS....

I load them to factory length, them shoot sub inch in my two Rock River Varmints.

We all shoot "sub inch". Lets just start saying we all shoot them sub 1/4 inch.. I do remember seeing your targets in the black rifle challenge.. Top 10 right...

Thanks, starting tomorrow with 50 grain vmax,

but heading toward the 69 grain Sierra OTM's I have on hand.

I'm actually set up @2.270 for my bolt 700,

2.270 works in the mag (just barely).....

Any issue there that I might want to know about?

Same here. Right around 2.25. With AR's I don't even measure to the land, no point in it.

Yeah, not all bullets are the same length. Match bullets may vary by over .01". They'll shoot well, but if you are playing too close you could get a round stuck in your mag. Measure at least a dozen before you go pushing the limit on length.

Don't worry about anything to the right of the hundredths place for OAL, the bullets aren't uniform enough and it doesn't make any difference anyway.

I have a UK 30 round steel magazine that I can load to 2.290". I played with a couple loads, but could not tell any difference in accuracy. Did not really pursue it as 30 round mags are a pain for bench shooting and I prefer 20's for a walking around magazine.