Lapping rings really, really matters (unless the mounts are truly,truly bad) on a gun that's capable of bughole groups & very damn few AR's meet that criteria.
So if it soothes your mind, lap away. Likely your AR will never know the difference.........if you don't think better mounts are more concentric & straight, & you intend to lap them anyway, because they're all bad, then just go buy some Tasco's & lap 'em in.
MM
