28 nosler donuts

BClrh

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Jan 14, 2017
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I am getting donuts in my 28 nosler brass. If I take a fired round and try to slide a bullet in the neck it will slide in till the bearing surface gets to the neck shoulder junction then it hits the donut. Not all the pieces have the same problem. On some of them the bullet will go in and you can barely tell and others have resistance but they will go in.

Anyone else experiencing this? Any insight on donuts, causes and what to do about them would be appreciated.
 
New brass comes with donuts inherent to it's manufacturing process. So unless you intend to fix this(through neck turning), it's best to avoid downsizing of it, and seating bullet bearing into it.
 
New brass comes with donuts inherent to it's manufacturing process. So unless you intend to fix this(through neck turning), it's best to avoid downsizing of it, and seating bullet bearing into it.
My brass didn't have any for the first few firings and they range in severity at this point. I would bet that if I culled the ones that a bullet wont slide into and kept shooting the rest they will get to the same point.
 
The big question is your bullet seated past the doughnut? If not don't worry about it. IF you want to keep everything the same then i would purchase a LE Wilson trimmer with the inside neck reaming tool. Pretty slick.
 
The big question is your bullet seated past the doughnut? If not don't worry about it. IF you want to keep everything the same then i would purchase a LE Wilson trimmer with the inside neck reaming tool. Pretty slick.
My throat length forces me to seat past the donut. I have been looking at reamers and I seen a video on the Wilson and it does look slick.

I have a forester trimer and they have a inside neck reamer that attaches to it but I don't know if it is as precise a system as the Wilson.

I was also eyeing up the K&M neck turning set up with the carbide cutting pilot to get things straightened out
 
My throat length forces me to seat past the donut. I have been looking at reamers and I seen a video on the Wilson and it does look slick.

I have a forester trimer and they have a inside neck reamer that attaches to it but I don't know if it is as precise a system as the Wilson.

I was also eyeing up the K&M neck turning set up with the carbide cutting pilot to get things straightened out

If you're considering neck turning I picked up a PMA Tool Model A. I haven't owned others but I got this based on bench rest guys. I figure if it's a top choice for them it's fine for my tinkering. It'll run you about $150. I got mine because I bought a bunch of 1x fired RP brass for my 7SAUM.
 
I use the PMA neck turners (Model A and B) but they don't make a doughnut cutting turning mandrel. So, I bought a .263" chucking reamer and cut the doughnuts in my 6.5 SS after sizing and using a proper sized sizing mandrel. Since I use a Giraud case trimmer I don't have the option to cut inside doughnuts while trimming so I've got to do it as a different step. It's a PITA but it works.

I haven't used the K&M turning tool but I'd probably buy one with a cutting mandrel if I didn't already five PMA turners.
 
There are inside and outside doughnuts. You typically get those only when you're forming brass to another cartridge and pushing the shoulders around.

In the 6.5 SS, you push the shoulders back which causes some of the former shoulder to become the neck. It will cause that new portion of the shoulder to be thicker than the rest of the neck. It requires you to turn the necks to the same size all the way to the shoulder.

Sometimes, you'll also get the same thicker case inside the neck down by the shoulder. If you don't remove this and your bullet gets seated past this thicker part, you'll increase pressure. So, you have to figure out a way to cut the inside doughnut out. That's where the reamer or cutting mandrel on a neck turner comes in play. Outside doughnuts are easy to fix, inside ones can be a PITA since your neck needs to be a specific inside diameter so you don't thin your necks by reducing the thickness with your reamer.
 
My brass didn't have any for the first few firings and they range in severity at this point. I would bet that if I culled the ones that a bullet wont slide into and kept shooting the rest they will get to the same point.

IMO you are resizing the brass too much. If you bump the shoulders back to far on cases with steep shoulder angles. It will easily form inside donuts. I have this problem with 2 WSMs. If I resize the brass back down far enough from the 1st one, so it will fit in 2nd, it will donut every time. If I keep the cases separate and only bump back .002, they don't get donuts.
 
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