Any movement between the can and the muzzle adapter is going to be bad for accuracy . The problems with AAC's mounts goes way back , that's why they keep adding teeth to the ratchet surface but the issue is in the tapered seat dimensions . QD cans will never be my first choice in a precision rifle can .

But back to the part where the rifles group tightened back up when the fundamentals were followed really is an indication of shooter error . The biggest causes of vertical dispersion are bipod preload , rear bag technique , and cheek weld issues .

I shoot all 3 of my precision rifles exclusively suppressed , 260 , 308 , and 338 with a 30P and 338BA . None of them will throw shots out of the group regardless of how fast I shoot them . One of the best groups I've fired out of my 260 was 5 rounds in about 30 seconds while sharing a chrono and was more interested in the numbers than group size , put all 5 into just over 1/2 inch at 200 .

The reduction of recoil and the way the recoil impulse is changed with the suppressor on can and will lead to sloppiness in the fundamentals because the rifle is more forgiving to shoot but they are just as important .

There is no reason to sacrifice accuracy for the noise reduction .