Originally Posted by sambo3006
I had the same problem as sniperjwt with my Remington factory barrel. I could not stabilize the 180's. I shot .6" at 100 yards and figured they might really group at longer distances after they "went to sleep" but my 500 yard groups off sand bags with my Leupold 6.5-20x SF scope looked more like shotgun patterns. I was disappointed but that is the way it goes.
I don't believe that your poor groups at 500 yards were due to stability. If they were grouping .6" at 100 yards, that proves that they're stable from the muzzle. Until they slow to transonic speed (in this case, 1000 yards +) stability will not be a problem.
I would guess that your poor groups at long range might be due to bad velocity variation, or scope parallax not being adjusted properly for the range, or something else besides stability. In other words, I think that whatever was causing the excessive dispersion at range is a 'solve-able' problem.