Reloading with Redding Bushing Dies?

Discussion in 'The Basics, Starting Out' started by MAELTY, Apr 4, 2004.


    MAELTY Active Member

    Mar 14, 2003
    When preparing cases using a bushing die, and also neck turning after, would this change the size of the neck bushing?

    I've yet to use this method and the primary components that I will be using is Winchester brass and the 162 gr AMAX or 7MMWSM.

    I read Reddings Tech Talk info on how to select the proper neck size bushing and I'm thinking that , nothing should change. Am I right?

    I'm not shooting a tight neck now as I have yet to experience any tight chambering problems after neck sizing. I do bump the necks back once in a while.

    My main thrust is trying to do this reloading stuff the right way, and I know you know how, so fess-up and share your knowledge with me [​IMG]


  2. Brent

    Brent Well-Known Member

    Jun 12, 2001
    The neck bushing size needed will change if you want to maintain the same neck tension ()press fit).

    You thinned the neck when turning them, so neck tension will now be less... use a smaller buching ID now and you'll get it back though.

    I use about .001 tension is all, so a bushing of the same size or .001 smaller than the loaded diameter is what I use.

    If you don't have a tight neck chamber, the same size bushing as the loaded diameter should work better. It WILL size the neck down smaller than the bushing ID is why. The larger the neck diameter is when it enters the bushing, the greater the angle it enters it at, and it will usually end up a thou or two smaller than the bushing ID because of this. If the chamber's neck is tight, you will likely need a bushing with a smaller ID than you want the result to be because it enters the bushing with no angle and the brass springs back a thou or two. I generally use a bushing a thou or two smaller than the desired diameter in this case.

    A chamber's neck which is tighter than factory, but not enough you must turn necks for, bushings of a given ID will produce neck OD's of nearly the same size.

    My suggestion in a nutshell:

    Factory chamber -
    If fired brass = .010 or so over loaded rounds, use bushing with .000 - .002 ID larger than loaded diameter.

    Tighter necks -
    If fired brass = .003 - .005 or so over loaded rounds, use bushing with .000 (or +- .001) ID larger than loaded diameter.

    Tight necks -
    If fired brass = .001 - .003 over loaded rounds, use bushing with .000 - .002 smaller than loaded diameter.

    Now, that is for about .001, maybe .002 neck tension or interference fit, if you want more tension than that you'll have to stay on the smaller side of that.

    With some messing with it and measuring OD's before and after loading etc, you'll find what works pretty quickly. Redding could do a much better job at recommending a starting point IMO.

    If your necks get harder after 5 or more reloadings or so, this WILL change your neck tension, and you'll feel it too. Either anneal, or drop/increase you bushing ID to maintain it or stuff can change on the target.