It's not the rifle. It's definitely me. The 25 yard groups, despite my description were pretty tight. When I say 6 inches across, I am looking at the total spread between the two outer most impacts. I am not concerned with the 25 yard groups, not in the least. It's what happens when I get it out to 100 yards that is frustrating. I can't seem to hit consistently and I'm trying to figure out why.
How do you know it isn't the rifle? Define pretty tight. How many shots in the group? What sights are you using? Are you shooting prone supported, prone unsupported, from the bench, sitting, standing, using a sling?
Those A2 style barrels have some flex, and using a sling inconsistently can cause problems with accuracy. Sight picture could be a huge problem... it only take a very small movement to make a huge group out of a small group. If your sights are moving... then you will see odd groups.
How are your sights attached to the rifle? You said off the shelf stock... so what format are you using? A2, A4, A1? Carrying handle integrated? Removable carrying handle (one possible sourece of movement), flat top with rail and removable rear sights (source of movement), scope (rings not properly secured to the base causing issues, bad scope not holding adjustment)? Is your front sight stting on your gas block.. is it tight?
More to the point, what have you done to verify the rifle? I'm having huge problems believing that your technique is so shoddy that you are getting 6" groups at 25y without some sort of mechanical issue with your rifle. What does your rifle shoot group wise in the hands of a competent shooter?
If your rifle isnt using a free floating barrel and you're using a rest... inconsistent pressure could be causing your vertical stringing. Shooting a hot barrel in one of those pencil thin barrels can cause POI shift up or down as well. Left to right (poor trigger can do some... but not 6" worth at 25y). That sounds a lot like loose sights.
