Thanks for the info on the ammo issues.He started out with 168grn match ammo (I think it was FGMM, but not 100% sure) and had issues stabilizing it around the 800yd mark.....it shot fine up until then. Much past 800yds it was all over the place.
I floated him some M118LR (that's a 175grn load) and it straightened right up. No issues hitting the steel between 800-1,000yds.
This is not a SCAR-specific issue. I've seen it in numerous rifles over the years. Folks ask me if they will be able to reach 1,000yds with 168grn match and I just shrug and say, "Maybe". Never know until you try it.
I've run 168's to 1,000yds+ more than once, but in some rifles it ain't gonna work. 175's, on the other hand, always work.