How does a bullet seater set the OAL

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Lovesbeer99

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I'm asking this question because I was thinking of getting a Gracie or Girard case trimmer which trims brass indexed off the shoulder, not the full length of the case like traditional trimmers do. This means that each case can be a different overall length but according to research that is OK because the bullet in the chamber is seated from the shoulder not the rim. So this process is supposed to be more accurate.

But if the bullet seater is not also indexing off the shoulder than my OAL will be all over the place and inconsistant in the chamber right? How does this work?

Thanks in advance.
 
The shoulder should be set at a consistent length from the head. Bullet will also be set based on length from head. If the shoulder is consistent, then trimming from the shoulder will also be consistent.
 
Case length does not affect OAL in any way. The seater die does not index off the shoulder. No worries. Besides, the only length you need to worry about is from the ogive to the lands.

This means that each case can be a different overall length
No it won't. Size each case, trim it with the Giraud, the Gracey, or the Possum Hollow, all of which index off the shoulder, and you will find case lengths to be extremely consistent.
 
Seater pushes somewhere on the ogive of the bullet, exactly where depends on the shape of the plug and the bullet. Different nose shapes require re-adjusting the seater. The reference surface for any seating process I have seen is the base of the case. The shoulder location will not affect seating depth / OAL / crimp.
 
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