Took my Colt 6920 and my new RRA Standard A2 I got from Legal-Transfers on the EE to the range today, and all I can say is wow!  50 yds. prone I was getting 1-1/2" groups.  Black Hills 55gr. out of the RRA and XM193 out of the 6920.  Burned off about 600 rounds and it seemed like the 20" got much hotter than the Colt.  Anyways, I was highly impressed as I've always been a "Garand Guy".  Guess I'm full bore Black Rifle Guy now .  Something strange happened though:  When I put XM193 in the RRA 20" all of my groups were centered about 1" to the right.  Anybody had anything like this happen?  Why?  Just thought I'd share the joy and finally post a pic of my rifles.

POI can differ between different ammo. One time at the range I went from shooting XM193 to 69gr Georgia Arms match HP's and I was hitting dead center with the XM and an inch or two left with the GA.

Well, I can see bullet weight and powder affecting your POI elevation-wise, but I've never seen it happen on the horizontal before.  Thanks Yellow