neck sizing

tomL said:
Is there any difference in using a FL sizing die back off about one full turn in the press from the shell holder or using the neck die?

Tom
Click to expand...

You are describing what is called "partial full length resizing" where approximately 3/4 of the neck is sized. This will reduce the case body diameter slightly but not as much as full length resizing.

The trick to "partial full length resizing" is to not reduce the case body diameter enough that it squeezes the case shoulder forward. Many reloaders do not know this but this method supports the case body and case neck and reduces case neck runout.

Depending on your chamber diameter and die diameter you wiil need to experiment and find out how far down the neck you can size before the case shoulder starts to move forward.

wm05ArY.gif


 
Try it. Every chamber/brand of dies is a little different. The key is consistency. Minimal resizing while still comfortably chambering is ideal for a bolt gun. As long as the neck is fully sized and it’ll hold a bullet. Semi is another story.
 
Redding competition shell holders makes this process a breeze. The nice thing is you can then do it with any cartridge that uses the same sized shellholder. No need for a NS die for each cartridge.
 
Just make sure you check the die your using for "runout".

You can neck size all you want but if your mandrel is off you will have rounout on your finished rounds.

I would recommend a Redding shoulder bump die and LEE Collet Die and a Redding competition(,or Forster) seatimg die.

Your press can also be a source of runout.
 
You must log in or register to reply here.
Back
Top Bottom