overall case length question

[denton]

Every gun, and every bullet is going to be different. I have one 30-06 where there is .100" difference in where a Hornady bullet touches the lands, vs. a Sierra.

For each rifle you load for, and each bullet you shoot, you should measure the COL (cartridge overall length) that just puts the bullet out to the lands, and load about .030" shorter than that. You may find that this is longer or shorter than what is in the book. Loading clear out to the lands will cause excessive pressure.

To measure the distance to the lands, fully form an empty case, and cut a slit on both sides of the neck, using a Dremel tool and abrasive cutting wheel. Knock the burrs off. Seat a bullet just barely into the neck. Load it in the gun, and close the bolt. When you extract it, the length of the dummy cartridge will be the COL that puts that bullet at the lands. Do it a couple of times, just to be sure your readings are consistent.

After you have used the case a couple of times, you will have to gently tighten the neck tension with a pair of pliers or something.