Just wanted to make sure, some of us Old School guys bedded both the action and barrel. Placing a pressure pad under the barrel sometimes helped dampen vibration to improve accuracy too.Umm, it's probably both. Bedded action and free float barrel is pretty much the standard for accuracy.
Your rifle shoots sub-moa with cheap ammo and you're complaining that groups open up with the expensive stuff?I don't believe it is. The thing is, it grouped well with only one type of ammo: Monarch steel-cased. I shot two groups which were sub-moa with that stuff, so I believe it is a rifle problem unfortunately.