Selecting the correct bushing

[fvalmostthere]

There are 2 methods i have found for selecting the correct bushing for your redding type s die.

Type 1: measure your case neck wall thickness, double it and then add it to your diameter. Ex. .015x2=.030+.264=.294

Now that you have your measurement subtract your desired neck trnsion and order that bushing.

Type 2 (better option)

Load up a round and measure the outside diamter of the case neck. Then subtract your desired neck tension and order.


I did the first method with the exact example i gave and ordered up a 292 bushing to have .002 neck tension. Finally tried to load up some 140 hybrids in some once fired brass and could slide the bullet in and out like i didnt even size it. Grabbed a loaded round in some new brass and measured the outside to .291. Went to exchange the 292 for a 289 and it was going to cost me 10 in shipping, so now i have 2...

Hope this saves someone from making the same mistake i did.

 

[fvalmostthere]

Thats the method i used and i ordered a 292.

After measuring a loaded round i should have ordered at 289...

I ordered the titanium nitride one so $27. Not a huge deal but now i have to wait again.

 

[mdmp5]

The only way to do it is to seat and measure. trying to calculate sets up for error

 

[TheGerman]

Have been going through and refining this process a bit lately. While the quick answer is to measure a loaded cartridge and subtract .001, thats not usually what your case neck diameter ends up being due to spring back and varied neck wall thickness.

The long answer, from probably 100 IM's with Padom about specifically this is to take the button out of your FL die with the bushing and start with a bushing (kind of a SWAG as to the diameter). Use this die to bump the shoulder and put the exterior tension on the neck. Then put the case through a mandrel and measure what your case neck diameter actually comes out to. Change out the bushing until you get whatever the final diameter you want is.