That rifle has an 18" barrel but a fairly fast twist rate. I would try Federal Gold Medal Match 168 grain rounds. I don't have that rifle, but I have a Remington 700 with the same length barrel but a slower twist rate (1:12). If I keep my shooting to 500 yards or less, it shoots sub-MOA with the Federal loads and my hand loads.
However, with your 1:10 twist, you can even go up to the 175 gr projectiles all the way up to 500 yards+ and stay supersonic (if I recall).
If you want to stretch it out further, drop down to the 150-155 grain projectiles and you can use it on deer and elk up to 400 yards.