DONUT ?

[Link]

Gooday

I have a question = If you neck up to 30 cal w a mandrel, necksize using a bushing then fire in a no turn chamber.


Then after a couple of firings go to take a cleanup turn on the necks and find a donut in the Inside from where the neck and shoulder transect.

Will there be a ill affect if you use a light enough bullet that does not seat even close to the donut.

I hope you can follow?

thanks

 

[jonbearman]

Clean it out with a drill bit that fits the inside of the neck . Or you can get a reamer to clear it. It definitly interferes with the powder burn.I would find away to get rid of it.Sometimes you can just send a tapered expander ball down it and it irons it right out if it isnt real pronounced. I am sure others will chime in witha better solution.

 

[artbosco]

I have a question = If you neck up to 30 cal w a mandrel, necksize using a bushing then fire in a no turn chamber.

Then after a couple of firings go to take a cleanup turn on the necks and find a donut in the Inside from where the neck and shoulder transect.

Will there be a ill affect if you use a light enough bullet that does not seat even close to the donut?

An ill effect? No. In short range benchrest when shooting the 6PPC for Extreme Accuracy, we don't worry about the donut because our bullets mainly seat in the forward most 1/2 to 1/3 of the neck.

The only time you run into problems is when you try to seat them so far in that the donut obstructs the seating.

 

[amamnn]

Since you mention 30 cal I am guessing that you might be forming 30BR from 6BR cases? If so, you might find the K&M mandrel made for this type of project to be of some use; it can be adjusted to stop before forming the DD and a reamer can then be used to finish.

Myself, I hate for things to be done wrong--even if the bullets I use are FB and never contact the DD I MUST eliminate it....(Peter Lorrie voice--oh yes it must be eliminated!!!!!!)