Let's talk about the "dreaded donut"

[sp6x6]

That is a major flaw in the Hornady COAL gauge. I pondered that for a long time and just kept loading (thinking I was seating .010" off the lands) because they didn't point that flaw out in their instructions.

Finally, I took some other measurements and cross-checked and compared and convinced myself that the gauge was reading ~.015" short of what it should.

The bottom line is that the Hornady "modified case" is short by some amount. But, not all of them by the same amount. So, you get a good reading from the front shoulder to where the ogive meets the lands. But, the distance from the shoulder to the case head+headspace+bolt face varies.

This may not always be true. But, it sounds like you ran into the same problem.

-- richard

Lets put it this way, its not helping me out, added to my problems Now I know. It is like reading the shoulder, I am getting slight different data on where I READ from shouler to neck, based on bushing size and donut pushing with bullet , brass around. Trying to sort it out. I have worked with the same 15 brass the whole time and I shot some hot.Which is probably not helping. Just trying toget a go to laod and wanted to try 285 also. I got 300 hyb. to go 1'' @ 400 IN 2 diff. 3 shot groups. Velocity was about 2665, seemed slow, but 26'' barrel, I'M ok with it.I THINK I just need to ream inside neck, and watch for the donut, I dont plan on going hotter load either which should help.

 

[Daves22-250]

This is my first post. I read this thread with much interest. I have a few questions to ask and I'd like your opinion as well. I'm about to start neck turning my 22-250 Rem. brass and I've never done this before.

I've been using the Foster Bushing Bump Neck Sizing Die with the .251 Neck Bushing. Attached is an example of the Bump Die.

It appears to me the unsized part of the neck is now the new shoulder. I measured this unsized part to be .259 (.008 over the sized neck). Now if this is the new shoulder, I'm considering turning the neck just into the new shoulder. With the bullet pressed in, the neck only increases to .252.

I'm aware that normally brass is full length sized and expanded before turning the necks.

1. Should I still full length size the brass before tuning the necks?
2. Would it be reasonable to neck turn to the apparent new shoulder?
3. Just how thick is a donut when it forms?
4. With this die, where would the donut most likely appear?

 

[SBruce]

If it were me, I would turn the necks prior to your current sizing process, and turn them just into the neck/shoulder junction (the real shoulder, not the new false shoulder). If you get into the new false shoulder with the cutter, it will make the brass very thin at that point.

I would also FL size and use the expander mandrel or the proper expander die prior to neck turning.

I am not familiar with how your particular die works, but the bushing dies I've used, only bump the shoulder if the entire neck gets sized. I am unclear on how you're getting a false shoulder on the neck and still bumping the shoulder datum back.?

 

[rscott5028]

If it were me, I would turn the necks prior to your current sizing process, and turn them just into the neck/shoulder junction (the real shoulder, not the new false shoulder). If you get into the new false shoulder with the cutter, it will make the brass very thin at that point.

I would also FL size and use the expander mandrel or the proper expander die prior to neck turning.

I am not familiar with how your particular die works, but the bushing dies I've used, only bump the shoulder if the entire neck gets sized. I am unclear on how you're getting a false shoulder on the neck and still bumping the shoulder datum back.?

+1

-richard

 

[Mikecr]

It appears to me the unsized part of the neck is now the new shoulder. I measured this unsized part to be .259 (.008 over the sized neck). Now if this is the new shoulder, I'm considering turning the neck just into the new shoulder. With the bullet pressed in, the neck only increases to .252.

If your chamber put the unsized necks at 8thou over, then this is not a false shoulder, not a donut, and there is no reason to turn into it or pay it any mind really.

With this die, where would the doughnut most likely appear?

Why would this die produce any donut? Does it size the body near the webs much?

 

[Daves22-250]

If your chamber put the unsized necks at 8thou over, then this is not a false shoulder, not a donut, and there is no reason to turn into it or pay it any mind really.


Why would this die produce any donut? Does it size the body near the webs much?

As shown in the picture above, the only part sized is approximately the top .210" of the neck and the shoulder. The rest of the brass is not sized at all. The round chambers fine. If I understand this thread, I don't think there is a reason for donut to build.