Adjusting OAL after crimp is set

I

Ike Clanton

New member
I had my LNL seater/crimp die all set up for 45 colt. As I made a few rounds today I decided to shorten the OAL just a smidge from 1.600 to 1.590. I just twisted the seater knob a little bit and got the desired length. I realized after my batch that I had not reset the crimp. Will it make a difference. It appears they are still crimped the same amount. However for future rounds I’d like to know if I need to set the crimp again after adjusting OAL
 
Sit back,have a cup of coffee,study the process.
The die body controls the crimp. The lock ring locks it to the press. The cartridge case gets the crimp. It is separate from the bullet.
You could put the same crimp on the case with the seater stem removed from the die. Same crimp (probably) with no bullet.

The seater stem moves independently from the die body and does not contact the brass. It does not crimp. Moving the seater stem only matters if you move the crimp groove too much.

Now,if you move the die body down,you will increase crimp,you will reduce length over all,but you will not change bullet seating depth.

Clear as mud?
 
If the OP is using bullet w/ a crimp groove, just leave the die body where it it (just having
seated/crimped a bit long), release the ram, and screw the seating stem down just a skosh,
then raise the ram again.

No problemmo.
 
Yes clear as mud haha. So if anything I slightly increased the crimp and to get it back into spec I would back off the crimp adjustment a smidge?
 
If you do not change the height of the die body,you do not change the crimp.

Crimp is about the height of the shellholder,the die body,and the length of the brass.

I'm trying to help you understand how to answer the question for yourself,rather than just giving you the answer.

If all that is true, then making an adjustment of the seater stem /bullet seating depth/LOA will have no effect on the degree of crimp. That(bullet seating) is independent of the die body crimping the brass..

Just remember if you increase the crimp by screwing the die body in deeper,you will slightly shorten LOA.

So,yes,you can seat your bullet a little deeper by just adjusting the seater punch . The crimp will not change.

OK it dawned on me. You see a change in the crimp after you do the adjustment. You will,because the crimp has already dug the case mouth into the bullet. Seating bullets deeper after crimping will confuse you.
Load another round from scratch after making the adjustment at the seater stem.Your crimp should not need change.
 
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Crimp adjustment (i.e., die body position) has nothing to do w/ changing OAL.
Leave the die body where it is and adjust the seating stem.
 
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