Measuring seating depth questions

[SavageLapua]

I'm using a Hornady OAL Gauge to find the length from base to ogive on my 338 Lapua... Now, my question is, when I'm pushing the bullet to the lands, it will make contact, but won't mark the bullet. I can push it in with some resistance, then it will stop and mark the bullet. Would that first stop be free bore? And the second, the lands?

 

[Bob 964]

Re: Measuring seating depth questions

I know exactly what you are going through. When I first started using my OAL gauge I didn't know whether to stop on first contact or stop when the rod stopped moving. The instructions tell you to "tap" the end of the rod a couple of times when you feel contact. It's tough because you are trying to "feel" something that you have never felt before and have no idea what it is supposed to feel like. I took a number of different measurements and got too broad a range of different measures. I didn't know whether to $#!T or go blind.

So I followed some advice of others on this forum and, using a Dremel, cut a slot through the neck of an empty unprimed case down to the shoulder. You can then put a bullet in the neck of the case at a very long length. Slowly close and lock the bolt. The bullet will touch the lands and the closing bolt will move the case forward. After a few seconds, slowly remove the case and bullet and measure in a bullet comparator and caliper. I repeated this process 10 times and got 10 pretty consistent measures. At least I now had a ballpark figure.

This gave me some idea what measures to expect using the OAL gauge. I then repeated the measurements using the OAL gauge until I started getting measures consistent with those I got using the slotted neck. This helped me develop the proper "feel" when using the OAL gauge.

 

[SavageLapua]

Re: Measuring seating depth questions

Got ya! I've made the slotted case already. Just wasn't sure exactly which one I should be going off of. (I'm not really that new to reloading, but I have never gone this "in depth").

Thanks Squarenut!

This would certainly explain my issues over the weekend with my reload tests...

 

[hntbambi]

Re: Measuring seating depth questions

Seating the bullet with the bolt is jammed into the lands. Cover the bullet with soot from a lighter or candle and seat with the bolt. You will see the lands show up very plain. Adjust your die and repeat until you are just kissing the lands and that is 0" jump.

 

[Rando]

Re: Measuring seating depth questions

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Hntbambi</div><div class="ubbcode-body">Seating the bullet with the bolt is jammed into the lands. Cover the bullet with soot from a lighter or candle and seat with the bolt. You will see the lands show up very plain. Adjust your die and repeat until you are just kissing the lands and that is 0" jump. </div></div>

this is the best way imo. i use a black sharpie.