RE: Bore sighting
An easy way to sight in was shown to me by a Gunsmith that claimed he could sight in with one shot. He would anchor the rifle in a vise and line the scope to dead center on the target. Shoot one shot and then move the reticles in the scope to match the hole in the target. Yes, it works.
You can literally shoot a clover leaf or less. No plug pulling involved.
Rock Lock