Mind you, my experiences are Cold War vintage.
But keep in mind that this isn’t a sniper rifle, and at no military shoot I participated in with my issued Uzi did anyone measure something as exotic as groups, they just counted hits on target.
And in that context, the fact that the bolt goes forward in a straight line along the line of fire probably mitigates any serious effect on field accuracy. As I said in my earlier post, surprisingly accurate; we mostly shot single shot and short bursts, and got yelled at if the bursts were longer than two or three rounds.