So I ordered a 30 mm lapping tool today for my soon to be received SWFA scope for my .308 bolt gun. My question is that I have three AR's with 30 mm rings and one piece mounts that came with the 1" inserts that I am using because I am running Nikon 1" tube scopes on them. Is it really necessary to lap those kind of rings or do the inserts (plastic of some sort) take up the slack, especially since I am only shooting my AR's out to 300-400 yds. max?