20 BR

[Hippy]

Just received my 20 BR back from the Smith---wanting to know what Neck Diameter the "Blue Box" Lapua will be after necking down to 20 Cal--Needing to order bushings

What is the BEST way to size down to 20 Cal ?


Thanx,
Jim

 

[Wirelessguy2005]

There are a few ways to get from 6mm down to 20 but the easiest i have found is running the brass thru a 6br FL die with the guts removed followed by a 22 BR FL die with a carbide expander button and finally thru a 20 BR FL die with a carbide expander button. After these 3 steps the lapua blue box should mic at around .231 - .232 at the neck. You can also accomplish the same using multiple bushings, i have used this method but it takes more steps.