I always run a Sinclair expander mandrel through the necks as the last step before seating. But I found this does not push out the donut, at least not all the way. The Sinclair expander mandrel die does not support the case neck on the outside, so I think the brass is elastic enough that donut stays on the inside.
Bushing Dies vs Non Bushing Dies
- Thread starter jayquiver
- Start date
I always run a Sinclair expander mandrel through the necks as the last step before seating. But I found this does not push out the donut, at least not all the way. The Sinclair expander mandrel die does not support the case neck on the outside, so I think the brass is elastic enough that donut stays on the inside.
Well in that case, wouldn't a pass through a non-bushing neck or FL die push the donut out to where it could be removed by another neck-turning?
no, because the bushing does not go all the way down to the shoulder, and, if you were to cut that donut off the outside you would end up cutting the neck off the case as the base of the neck is not sized and is expanded to the size of the chamber.......ask me how I know......
And if you have your own reamer spec'd properly, the donut is a non issue. With my PPC and 30BR if there is a donut, it does not matter. The base of my bullets are far from close to a donut if one happens to occur.
The joy's of knowing what type of bullet you want to shoot and getting the correct info when you talk to people.
The joy's of knowing what type of bullet you want to shoot and getting the correct info when you talk to people.
And if you have your own reamer spec'd properly, the donut is a non issue. With my PPC and 30BR if there is a donut, it does not matter. The base of my bullets are far from close to a donut if one happens to occur.
The joy's of knowing what type of bullet you want to shoot and getting the correct info when you talk to people when you decide to.spec your own reamers....jmo
The joy's of knowing what type of bullet you want to shoot and getting the correct info when you talk to people when you decide to.spec your own reamers....jmo
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308 win run at elevated pressure for FTR... brass flow is impressive.
My process is to use a Lee collet neck die and outside neck turning. I turn at least every 2nd firing... every firing is better when I am not lasy. You can see the cutter touch the base of the neck after pretty much every firing even though it doesn't touch anywhere else on the neck. I will cut into the shoulder and has been mentioned, gives the brass flowing a place to go.
You really can't use bushing dies effectively if you are also not going to turn your necks... brass flow screws with your thickness and it will happen with the next firing.
Jerry
My process is to use a Lee collet neck die and outside neck turning. I turn at least every 2nd firing... every firing is better when I am not lasy. You can see the cutter touch the base of the neck after pretty much every firing even though it doesn't touch anywhere else on the neck. I will cut into the shoulder and has been mentioned, gives the brass flowing a place to go.
You really can't use bushing dies effectively if you are also not going to turn your necks... brass flow screws with your thickness and it will happen with the next firing.
Jerry
Yes, the solution to the problem is clear if you can always seat your bullets ahead of the donut. That's not always possible, however, so dealing with the donut directly is sometimes necessary.
If you have a set of bushings and you have one that is the size of the neck in the chamber, you can use it as a go gage. Or you may prefer to use a bushing that is one or two sizes smaller than your neck so you have clearance.
If you can slide that bushing all the way down the neck of a loaded round, your donut is of no concern, from the view of safety.
If the bushing stops short of the shoulder, then you have a donut and need to address it.
If you seat into the donut, it can mess with velocity and seating depth.
One way to fix a live round is to chuck it in a drill and run a small radiused file into the bottom of the neck until the bushing will slide all the way down.
The ideal chamber will allow bullets to be seated ahead of the donut which makes its presence irrelevant.
If you can slide that bushing all the way down the neck of a loaded round, your donut is of no concern, from the view of safety.
If the bushing stops short of the shoulder, then you have a donut and need to address it.
If you seat into the donut, it can mess with velocity and seating depth.
One way to fix a live round is to chuck it in a drill and run a small radiused file into the bottom of the neck until the bushing will slide all the way down.
The ideal chamber will allow bullets to be seated ahead of the donut which makes its presence irrelevant.
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