help with loading brand new brass

[Uncle Ed]

what is a small base die ?

I buy once fired Lake City 5.56 and 7.62 brass and size the cases the first time with a small base die.

In a semi-auto the resized case body diameter should be .003 to .005 smaller than its fired diameter. This ensures the case will spring back from the chamber walls and extract reliably.

That being said most semi-autos, pump action and lever action rifles have larger chambers. Meaning in most cases a small base die is never needed. "BUT" nothing is written in stone and chambers and dies vary in size. Example I have a standard Lee .223 full length die that will reduce the case body smaller than my RCBS small base die. Also as the brass becomes older and work hardened you will have more brass spring back after sizing and "might" need a small base die.

 

[onelastshot]

I run all my new brass through a full length sizing die. I've never had an issue with new brass.

 

[T-shooter]

I prep new brass just like any other except when neck turning, I'll go a couple thousands thicker if I can get 80% or so of the surface cutting. Then when fire formed, do it all over again and recut the necks to the desired thickness.