So if I understand your concerns it would be that an aftermarket bolt head would have different dimensions from the bolt face to the datum(action recoil lug). Legitimate concern. If I remember I have seen a difference of as much as .025". That would be anywhere up to 180* rotation in or out. Therefore, depending on your brake type you would need to have it timed by machine work, adding shims or adjustable locknut.

This can be done by removing material off of the face on the barrel or the face of the brake. For each .001 removed the brake will rotate 7.2*...or add shims using the same formula..