I have to agree with BSA here, and MM too.

I would not expect Federal M193 to shoot MOA, but I am pretty damned sure I cannot shoot even the best ammo in an AR with iron sights and get anywhere near MOA even with the most appropriate rest under the rifle. Throw in the different ergonomics of an AR (I am still trying to find "the zone" and I've been shooting ARs casually for over a decade) on top of the open sights and less-than-stellar ammunition, and I am right there with you holding a target that looks something like that.

I'd put a scope on it and feed it some ammo with a reputation for decent accuracy and try again before messing with the barrel or giving up.

Don't be the darkness.

America will perish while those who should be standing guard are satisfying their lusts.