Re: Wilson Neck Sizer Bushing Help 7mm-08
~ Contact Wilson and let them know you want a Bushing Neck Die
~ HandLoad 3ea (I did 4ea) 7mm-08 rounds using your Winchester cases
~ Fire the 3ea rounds & ship to Wilson. Fired cases allow selection of the proper bushing sizes (ie. ideal neck tension)
Example:
For my 300WM, using Norma cases, Wilson return shipped the following: 229 bushing (.329) INSTALLED in Bushing Neck Die, 230 bushing (.330), and 231 bushing (.331). I asked for these two addl bushings ($20ea) for neck tension options.
You can calculate bushing size selection via two methods, referenced from the Wilson Instructions accompanying the Die.
Option 1: Measure your loaded round at the neck. The micrometer reading will indicate bullet diameter, plus twice the wall thickness of the neck. The bushing diameter must be obviously LESS than this, and we selected 0.003" smaller. Figuring the spring back of the case neck AFTER sizing, it would yield ~ 0.002" 'grip' on the bullet.
Option 2. Bushing Size = Bullet Diameter + [(Neck Wall Thickness x 2) - 0.003"]
Note: Assuming you are planning to use to Bushing Neck Die with the Wilson Chamber Type Bullet Seater. If this is the case, be sure you try an UNLOADED case in the Bullet Seater (regardless if the case was NO or FL sized). Why? Need to confirm that your case can be pushed until it is flush with the bottom of the Seater. IF it won't go flush with the Seater, or if it requires a small screwdriver to remove under the rim/head, THEN the Bullet Seater needs to be opened up by Wilson to fit your cases. Recall, the Bullet Seaters are fabricated to SAAMI specs for max allowance on cartridge manufacturers. BTW, I sent my Bullet Seater to Wilson (because it needed to opened up) when I provided them the 3ea FIRED cases needed for bushing selection. Wilson "opens up"'the Bullet Seater free of charge.
Again, recommend calling Wilson first and let them know what you want to achieve.
Hope this answered your question.
Aloha
