I might be speaking out of line, being far less experienced than most of the arfcom gang here, but it would seem to me that if a laser bore sighter is only good for getting you on paper, then that laser bore sighter is either shiite or in need of alignment, which a decent one has adjustments for. Or you guys are using really small targets.
I could see if cheap ones might not seat in the chamber consistently, have issues with headspace or something, but mine works great.
Few things are more precise than lasers, which is why surveyors use them now instead of optical transits like my dear old dad used to use back in the days of Buddy Holly and malt shoppes.
To wit: I recently had an issue with a new AR w/ a front iron sight that was definitely canted to the left, and I bought a LBS to confirm, along with using my own eye to sight down the barrel.
The LBS agreed with my eye, but more importantly, also where the bullets were going at the range. Cant confirmed. I sent the rifle in for an FSB adjustment, which the company (fantastic service, quick turnaround, paid shipping both ways) did, and got it back within spec, though still a little bit off. Again, I sighted through the barrel by eye, then by LBS.. Judging by the LBS, I needed about 13 turns of the rear sight to zero it in. I then recentered the rear site, took it to the range, it was off about 3 inches; I moved the rear sight back over 13 clicks as measured at home with the LBS, and bingo, got a few bulleyes at 50yd.
Just be sure to test the LBS by carefully inserting, removing and reinserting, rotating it 1/4 turn each time. If it's true, the dot should not move as it rotates; if it does, the LBS needs adjustment and is untrustworthy until aligned.