Thread: Seating depth measurement problems

The first method you tried is quite unreliable, it takes quite a bit of pressure to leave marks on the bullet and if the case isn't tight enough, sometimes the lands can grip the projectile and pull it out a little.
I found blacking the projectile with soot from a candle flame and seating shallower, looking for the land marks to be more reliable.
I would trust the OAL gauge more than the first method you tried but the candle method is also very good.
Which ever method you use, do it a few times to make sure your results are repeatable!