Picture of "donut" inside case neck

[Cassidy]

Here's a pic of a "donut" from a case. Thought some may want to see one. Pic's a bit burry from my c/p but I think you can see it at the neck-shoulder junction inside the neck.

 

[rsbhunter]

Thanks for the picture , I always figured that is what they looked like, but luckily never had this problem. rsbhunter

 

[markm87]

Damn, damn dirty donut!

 

[NorCalMikie]

Either seat the bullets ABOVE the donut or push it to the outside and turn it off.
Better just to seat above the donut and keep shooting.
NEVER had a donut form as I shoot the lightest bullets I can get my hands on and load into the lands.
And I have LOTS of necked down brass with no donut issues.

 

[Crumster]

An old benchrest problem and solution.... turn your case necks a touch farther down. If I knew more about computers, I could show you with a simple diagram. If you know someone with a big Precision Shooting library, it's going to be there.

 

[DIBBS]

This has description/explanation of neck turning with some images. Many many much more knowledgeable folks on this site have been turning necks for years. I've only dabbled a little with it so I'll post a link and defer to the experts.


https://www.accurateshooter.com/technical-articles/neck-turning-basics/

 

[Spoonbill]

Currently going through this problem. Gotta figure out if its coming from reloading process and best way to fix the cases that Im having issues with

 

[AlNyhus]

Currently going through this problem. Gotta figure out if its coming from reloading process and best way to fix the cases that Im having issues with

The best way to fix the donut is to remove them. I use a reamer that's about .002 smaller than the I.D. of the fired neck. The reamer needs be guided and the case supported so the reamer removes the donut w/o touching the inner neck.

A Wilson case trimmer is an excellent way to do this. You can get a cutter from Wilson in any diameter you like. Or you can use a chucking reamer and make a guide bushing for the Wilson trimmer.

If you get a cutter from Wilson, be aware than a standard cutter will be about .002 larger than the buller diameter...that may or may not be what you want. Check the neck I.D. with a gauge pin and go from there.

If you have a lathe, you can put the Wilson case holder in the chuck and a chucking reamer in the chuck of the tail stock and do it by hand.

Hope this helps. -Al

 

[Olde Man]

I use my full length bushing die with the bushing removed. With your brass and press in your normal shoulder bump setting run a cutting mandrel from K&N in through the neck by hand and remove the donut. I use a drill bit chuck as a holder. You should not remove brass from the neck. This will remove the donut with some clearance because of the normal shoulder bump springback. Easy Peasy

 

[Spoonbill]

The best way to fix the donut is to remove them. I use a reamer that's about .002 smaller than the I.D. of the fired neck. The reamer needs be guided and the case supported so the reamer removes the donut w/o touching the inner neck.

A Wilson case trimmer is an excellent way to do this. You can get a cutter from Wilson in any diameter you like. Or you can use a chucking reamer and make a guide bushing for the Wilson trimmer.

If you get a cutter from Wilson, be aware than a standard cutter will be about .002 larger than the buller diameter...that may or may not be what you want. Check the neck I.D. with a gauge pin and go from there.

If you have a lathe, you can put the Wilson case holder in the chuck and a chucking reamer in the chuck of the tail stock and do it by hand.

Hope this helps. -Al

Will try to call Wilson later today. Thank you. Should I fl size my brass and not use my mandrel and then cut the donut out or use my mandrel first?

 

[Crumster]

Currently going through this problem. Gotta figure out if its coming from reloading process and best way to fix the cases that Im having issues with

It's not coming from your reloading process. I know this because, as I mentioned, it was happening to serious benchrest shooters who's brass never saw an arm leverage reloading press.

 

[Crumster]

It's not coming from your reloading process. I know this because, as I mentioned, it was happening to serious benchrest shooters who's brass never saw an arm leverage reloading press.

If you turn your case neck thusly, you won't have to worry about reaming, because the donut won't develop.

 

[AlNyhus]

Should I fl size my brass and not use my mandrel and then cut the donut out or use my mandrel first?

No...you do it on fired but unsized cases