Metal God
Member
- Joined
- Sep 12, 2015
- Messages
- 445
Measure the OD of the neck of your fired brass . If it's .008+ larger then your sized OD neck . You will need to size your necks in .005 increments or use the expander button when sizing to equal the necks . Yep I'm not kidding , I went through this with the Redding bushing dies and for reasons still not clear to me . For what ever reason if you need to size your necks more then .007 or .008 using bushing dies you either have to also still use the expander button or size the necks in increments of .005 or less . Meaning if your fired neck measures .318 and you want .310 , you first size with a .314 bushing then again with a .310 bushing .
I know this seems odd but it's true . The reason many have never heard of this is standard dies size the neck way to much and the expander is needed to size them back out resulting in removing that unevenness we see when using a bushing die without expander when sizing the neck down more then .007 to .008 .
But don't take my word for it , Read my thread on another forum and the corresponding emails to Redding .
https://thefiringline.com/forums/sh...ght=does+your+redding+type+sizing+die+do+this
Quoted from Redding email in link above
( I have pasted below a quick explanation of how this can occur.
It has come to our attention through customer calls and our own use of the bushing style sizing dies that in certain instances, a given neck sizing bushing will produce a case neck diameter that can be several thousandths of an inch smaller than the actual diameter of the bushing. This idiosyncrasy occurs when the neck diameter of the fired case is a great deal larger than the diameter of the neck sizing bushing, such as occurs when factory chambers are on the large side of the tolerance range. Typically, we have not noticed any problems until the case neck is reduced more than 0.008-0.010". (your fired case .254 - .245 bushing = .009")
Solutions include, increasing bushing diameter to compensate and/or the use of a size button. Reducing the neck diameter in two smaller steps by using an intermediate diameter bushing will also help. More concentric necks will also result using this method, as the case necks are stressed less during sizing. Don't forget to properly chamfer the inside and outside of the case mouths and apply a light coating of lubricant to the case necks before sizing. )
