Bullet seating pressure

9ptbuk

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Hello, I noticed when seating bullets into new brass that the pressure required to seat the them varied somewhat. I had run the bullets through a neck sizer to uniform the necks before loading . Will this problem be resolved once there fired once and resized again ? Is this common ? Thanks
 
Hello, I noticed when seating bullets into new brass that the pressure required to seat the them varied somewhat. I had run the bullets through a neck sizer to uniform the necks before loading . Will this problem be resolved once there fired once and resized again ? Is this common ? Thanks

Yes and Yes

always run new brass through you full length sizing die before loading the first time.

best method is to run an expander mandrel through the brass and then run it through the sizing die. Stretch that neck out a little.

If you really are serious and want to know what is going on then seat bullets with this

apfmdi01_2.jpg
 
I would add that, once your brass has been through a few firings the brass will gradually lose it's malleability. As the brass in the case neck hardens it becomes more resistive to the bullet and that increases the amount of pressure needed to seat it. Even with annealing there will often be some difference in a case neck's resistance to seating the bullet. Unless you keep your brass very well sorted into sets based on number of firings you will eventually find that bullet seating pressure varies to some degree within the batch of brass you're working with. The bench rest guys get all worked up about bullet seating pressure but, unless you're trying to put every shot in the same hole, I wouldn't worry too much about it.
 
Lube the interior of your case necks with Imperial Sizing Die Wax, to obtain more uniform bullet seating force, and bullet release force.

There are other things that can be done also to obtain better case neck tension/friction/force consistency, like case neck annealing and outside neck turning. The Imperial Sizing Die Wax is an easy one to implement.
 
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