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neck tension ?

For necks that have been turned  or unturned necks with  very consistent neck thickness, you obviously don't need (or want) the expander.

A couple of times with  unturned necks, I've seen less bullet runout by leaving the expander on. I then changed those expanders over to Reddings floating carbide expander balls.
 
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Whidden told me that expander ball or mandrel if they were the Same size he saw no diff on target
I use the floating carbide on my 223-- but use a mandrel on my 6BR. Both seem to be giving desired results--no turn necks on all
 
Generally, with a bushing die, the last thing to touch my necks is the bushing. No buttons nor mandrels for me. I think in some cases there might be a benefit but overall, I think we're just moving the brass more to neck it down, only to expand it back up. The bullet is my mandrel, generally. Most runout issues originate from over working the case, especially the necks. How would I use .002 neck tension and get .004 runout, for example. Just an example and yes, there are other factors but I say that to make my point more than anything. That being, to move the brass as little as possible.
 
Generally, with a bushing die, the last thing to touch my necks is the bushing. No buttons nor mandrels for me. I think in some cases there might be a benefit but overall, I think we're just moving the brass more to neck it down, only to expand it back up. The bullet is my mandrel, generally. Most runout issues originate from over working the case, especially the necks. How would I use .002 neck tension and get .004 runout, for example. Just an example and yes, there are other factors but I say that to make my point more than anything. That being, to move the brass as little as possible.
Would I be correct in assuming that you turn your brass? Perhaps the mandrel is only helpful if the neck thickness is inconsistent.
 
Would I be correct in assuming that you turn your brass? Perhaps the mandrel is only helpful if the neck thickness is inconsistent.
Actually, no..but I've done it in both. I've just migrated more and more to no turns after years of thinking I had to turn necks to be competitive. Perhaps if the brass is bad enough, it may show up but that brass has shown under .0005 out of round as well as piece to piece for several years and lot numbers. Come to think of it though...same with several cartridges. The only real common denominator is Lapua and I know some see different numbers with it. I posted some numbers on here maybe a year ago on the subject.
 
Runout can be caused by many things. You need to check your necks at each step to find where it being caused. Starting with a fired case. (I remove the expander ball). I found that Le Wilson Arbor press seating die was causing my runout. I can say its not the Arbor Press. But I tried many things to make the Le wilson die work. Maybe I got a bad one. I just decide to move on. Now my runout is .001 or less at near the tip of the bullet.
 
Right now I am running into a small issue with an old lot of Lapua brass vs the newer stuff. The new stuff is thicker and I'm dropping down a bushing size or two. I didn't have them, so they are on order...but I've been down this path before without issue. FWIW, SR BR is my primary discipline.
 
Runout can be caused by many things. You need to check your necks at each step to find where it being caused. Starting with a fired case. (I remove the expander ball). I found that Le Wilson Arbor press seating die was causing my runout. I can say its not the Arbor Press. But I tried many things to make the Le wilson die work. Maybe I got a bad one. I just decide to move on. Now my runout is .001 or less at near the tip of the bullet.
Yessir. I mentioned this on here within the last day or so but I'll say it again here. Most runout issues happen during the sizing op, not the seating. I suggested the guy to check a fired case and then go down 1 bushing at a time to see where the runout showed up. It was straight, as fired but got crooked when sizing the neck. 30BR and a lot of people run pretty high neck tension on them. Haven't heard back yet but he was gonna try it.
 
Yessir. I mentioned this on here within the last day or so but I'll say it again here. Most runout issues happen during the sizing op, not the seating. I suggested the guy to check a fired case and then go down 1 bushing at a time to see where the runout showed up. It was straight, as fired but got crooked when sizing the neck. 30BR and a lot of people run pretty high neck tension on them. Haven't heard back yet but he was gonna try it.
Haven't read your message on the subject. But its just my way of trouble shooting. As a electrician, in a industrial setting, we spent more time trouble shooting than doing actual electricial install. So first you need to verify if you have a straight chamber. and than just follow the process.
 
For turned necks, no expander. For unturned necks, I replace the fixed expander with the floating carbide expander ball.
This is what I do on virgin brass, to get a consistent (or more consistent) straight neck. Then I remove when sizing after firing. This is when bushings come into play obviously
 

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