Thread: Using comparator tool when seating projectiles.

Originally Posted by 6.5 CRD

Personally i wouldnt worry about trying to measure to the lands with a Hornady OAL tool, I have always just loaded a projectile long in an empty case, tried it in the rifle with a bit of vivid on the ogive and just progressively seated it deeper in the case and kept trying it in the rifle till the bolt finally closes nicely & faint mark of rifling on the vivid. Measured that BTO then knocked it back another 10 thou and started from there. At the end of the day you had a load that was working well in that gun most of the time with the issue being inconsistent seating depth due to measuring COAL rather than BTO. I would load a round at your original powder charge and COAL, use Hornady Item #B234 Comparator set to measure what that ends up being as a BTO measurement. Once you have that measurement, Load up a seating depth ladder close to what that measurement is, for instance if it measures 2.610 BTO, i would load a ladder 3 rounds at each depth from 2.619 down to 2.601 in 3 thou increments & go shoot them, Giving you a 18 thou spread in seating depth around the area that worked for you before. Surely somewhere in there you will find what works.

That makes perfect sense except for the issue of proud primers. Checked yesterday, sure enough, couldn't see with the eye but certainly sufficient at times to cause anomaly.