Do you mandrel after using an FL bushing die?

Schmo

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As the title says, for those that use a bushing die, are you still using a mandrel in a second step? Or is the bushing good enough for consistent NT?
 
I have to now because my 7PRC ADG brass is not very good, neck thickness variance at almost .002. I made a "mandrel" by turning down a .30 cal expander ball to .280". I put that expander in an old sizer body and screw it in so it sticks out far enough to just hit the neck. Minimum decapping mandrel from SAC is .281" but I may give one a try and see how my groups are with .003 neck tension.
Never did with Nosler 7stw brass, neck only, and wall thickness within .0005.
 
I took a dremel to my expander ball so that it’s .003 under bullet diameter. This way it only touches the neck if the case mouth is deformed.

I don’t use a mandrel and accuracy and SDs (6 dasher PRS) are as good as when I used a mandrel.
 
I took a dremel to my expander ball so that it’s .003 under bullet diameter. This way it only touches the neck if the case mouth is deformed.

I don’t use a mandrel and accuracy and SDs (6 dasher PRS) are as good as when I used a mandrel.
Do you just chuck the expander ball/de capping pin up in the dremel and take it down to desired OD with emory cloth?
 
Do you just chuck the expander ball/de capping pin up in the dremel and take it down to desired OD with emory cloth?
That would work-

But I put the dremel with a polishing head in a vice and turn it on and chuck the expander ball in a drill and spin it against the polishing head on the dremel.
 
You need to have something round go through the inside of the neck last, otherwise the inconsistencies get pushed to the id and your bullet run out increases. I still use a bushing die then a mandrel for my precision stuff, but I'm not convinced it is better than standard dies for accuracy.
 
For the past couple of years, I have used a mandrel after FL bushing dies in 2 of my more recently built rifles (6 CM and 300 WSM). They shoot smaller groups than the other rifles I reload (270 Win and 300 WM).

My experience is limited, but I believe the mandrel process will produce more consistent results. I recently purchased mandrels for the other rifles. Time will tell....
 
As the title says, for those that use a bushing die, are you still using a mandrel in a second step? Or is the bushing good enough for consistent NT?
I just use the bushing die, I have not realized any downrange benefit from running the brass through a mandrel station.
 
Do you just chuck the expander ball/de capping pin up in the dremel and take it down to desired OD with emory cloth?
200 grit sandpaper followed by a rag with a little polishing compound works great. Just take it slow, as its easy to overshoot! Remember that brass has a few thou of springback, so test frequently on sized cases till you get the desired neck ID. For hunting, i like 2-2.5 thou interference fit after running the mandrel in a bushing die-sized case.
 
That would work-

But I put the dremel with a polishing head in a vice and turn it on and chuck the expander ball in a drill and spin it against the polishing head on the dremel.
I like this idea. Drives me nuts on standard dies when you have a lot of tension getting back through the neck on the downstroke.
 
I like this idea. Drives me nuts on standard dies when you have a lot of tension getting back through the neck on the downstroke.
Most standard dies grossly oversize a neck prior to the expander opening it back up. This is the benefit of a bushing die, you can control how much or how little you're working the necks.
 
I remove the expander ball from all of my sizing dies. When sizing, I FL size my brass and then run them over a 21st Century mandrel. Depending on caliber I use a mandrel .0015-.003 under bullet diameter to set final neck tension.

I've used bushing dies and they are nice to limit how much the brass is worked. But for my hunting calibers, a standard FL die does just fine since I don't shoot them as much. But, for a gun I shoot a lot for fun then a bushing die is handy.
 
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