Home Forums Hunting & Shooting Ask The Gunwriters "dreaded doughnut" - MD

Will bushing dies eliminate doughnuts? Particularly because of how much of the neck they do or do not size?

Thanks Mule Deer, for the heads up on necked up brass.
I recently made some 338-06 brass by necking up some FC and Win 30-06 brass I had first annealed. It "looked" great, but this thread inspired me to check for doughnuts. Some of the Winchester brass (the first batch I've checked, in the process of neck turning) is particularly bad, so much so that the neck turning mandrel almost sticks in the case (which has already been passed over the sizing mandrel) when the turning mandrel reaches the constriction at the base of the neck. The brass is NOTICABLY thicker there.
I'm pretty fat on .35 Whelen brass so I am considering just abandoning necked up 30-06 (which I have a ton of, thus my desire to use it) and just go to necked down .35 Whelen.
I have some Weatherby headstamped 338-06 brass but I prefer to use that exclusively for one of my two 338-06s, and differently marked brass for the other, since their chambers and throats are slightly different.

Anyway, thanks again - this may explain why the "other" 338-06 has not yet shot as good as the one getting the Weatherby brass.

Rex

John, about an hour after I got back on this thread, I found your explanation in Rifle Loony News II, which has been my evening reading for a little while.

One well-known benchrest competitor claims bushing dies tend to encourage doughnuts, though in the article I read he didn't explain why.

That has not been my experience. In fact the dies for my own 6mm PPC benchrest rifle are Redding Competition, and I haven't detected any hint of a doughnut in the brass since starting to use it years ago. But then I don't shoot in matches. Instead I acquired the rifle to test what factors affect accuracy.

Some bushing dies stop shout of fully sizing the neck shoulder juncture, others have an angle that matches the shoulder and don't leave a ring un-sized. The Wilson bushings have the taper, I am not sure which others do.

When neck turning to remove a doughnut how much should you take off? Will just a 50-60% skim turning be enough or will that aggravate the problem?

An "un-sized" portion of the rear of the neck is not necessarily a doughnut.

If you use the technique I suggested in an earlier post, resizing the case in an expander-ball die, the doughnut will show up on the outside of the base of the neck, and be measurably larger than the rest of the neck. Setting the neck-turner to just skim most of the neck will eliminate the doughnut if you just turn the very top-end of the shoulder.

How many thousandths of an inch does this donut comprise of?

My size gets larger in the middle with donuts. That's why I don't consider them food. Be Well, RZ.

Depends on how large the doughnut is. It will vary.

When I was sizing 6mmBR brass up to 30BR , what had been a portion of the shoulder became the bottom of the neck.
Had I been loading bullets that seated their base below the neck/shoulder junction, I would have had a problem with the doughnut.
I turned all the necks for uniformity as I had a tight neck chamber and the excess was trimmed off neatly, including the doughnut.

[quote=Mule Deer]An "un-sized" portion of the rear of the neck is not necessarily a doughnut.
[/quote

If you use a conventional FL sizing die afterwards without the expander it can force the midriff bulge to the interior and form a doughnut. Some like the bulge as they think it helps to center the case in the chamber, not sure about this one though. I only turn necks if forced to and then my cutters have the bevel on them.

This is sound advice, however if you are one of those that is really fastidious, you may feel the need to anneal the brass before this process.Theoretically less spring back going over the mandrel and more doughnut to the outside. I say theoretically because I have not actually measured the difference...... but fairly certain the difference would be measurable.

BUT - does it matter?

Edited to add:
The difference in annealed and not annealed, that is, Will the brass "spring back" that much?

Was going to post pictures of 'lumps' vs, 'donuts' but posting pics here leaves a lot to be desired -Al

Imgur......

Forget the 338-06 just roll with the 35 Whelen

Imgur is what I use. It doesn't want to play nice here for some reason. Finally slapped it around and got it listen to reason.

'The lump' on the left: -Al

Al, just what are you manufacturing, there?

It guess would depend on how hard the brass is.

I just know if I’m going to go through the trouble of cutting off a doughnut, the brass is probably due for annealing.

Brass is the most labour intensive part of the whole reloading operation. Without good uniform brass , you can’t achieve bughole groups.