I have some 6.5 284 Norma BRASS THAT HAS BEEN FIRED FIVE TIMES. I aneeled it on the fourth firing. I originally turned the necks when I got the brass. I thought I would trim the brass and it hasn't grown at all. I thought I would for good measure, go ahead and re-turn the necks. When I slid the mandrill in, it only went in a little ways, and then stopped. I had to really force it in there with great effort. At the bottom of my necks there is like a rim of brass. I think I have heard this called a donut, but I don't know why this is there or how it got there. It wasn't there when I originally turned the necks. Any help would be greatly appreciated.
My Brass has a rim in the neck..WHY?
- Thread starter Lazerus
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kc0pph
Well-Known Member
Im no expert here but i would think your loads are a bit hot or there is a chamber issue.
Another thought are you neck sizing and doing it the wrong size? Might be when you seat the bullet it is making your ring... its out there but its a thought
Good Luck to you!
Another thought are you neck sizing and doing it the wrong size? Might be when you seat the bullet it is making your ring... its out there but its a thought
Good Luck to you!
D
Deleted member 46119
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The dreaded "donut" of brass moving up into the neck.
Get a neck reamer and ream the fired brass. Also known as inside neck turning.
or
Use a lee collet sizer wiith an oversized mandrel then outside turn the base of the necks.
I have 5 peices of 260 brass in my favorite lot that this happened to. I used the second method.
Get a neck reamer and ream the fired brass. Also known as inside neck turning.
or
Use a lee collet sizer wiith an oversized mandrel then outside turn the base of the necks.
I have 5 peices of 260 brass in my favorite lot that this happened to. I used the second method.
Mikecr
Well-Known Member
How are you sizing the necks(bushing/FL)?
How are you sizing case bodies?
When you initially turned necks, did you turn up onto shoulders a bit?
Why are you trying to turn again?
Are you seating bullet bearing into the donut area?
These necks that you're trying to turn now, have they been sized to fit the turning mandrel? How were they sized?
How are you sizing case bodies?
When you initially turned necks, did you turn up onto shoulders a bit?
Why are you trying to turn again?
Are you seating bullet bearing into the donut area?
These necks that you're trying to turn now, have they been sized to fit the turning mandrel? How were they sized?
I am sizing with a standard redding neck sizer. I am using a redding body die. I did not turn up onto shoulders a bit. I didn't know that was necessary. The reason I tried to turn the necks again is because after five firings and after being anneeled, I thought it wouldn't hurt. In fact, I didn't get any extra material off the necks. I now know it is probably unnecessary to turn the necks more than once, but I am glad I did otherwise I would not have learned about the donuts. Unfortunately, I have to seat my bullet into the donut area. The bergers that I was shooting three shots inside of a quarter inch, commonly. The cutting edge bullets I am now using are hovering 5 shots just under a half inch. They need to be seated 50 thousandths off the lans to become accurate. I am thinking that if I get the dounts removed, my group will tighten up quite a bit. I looked and it doesn't look like Lee makes a neck sizer for a 6.5 284 Norma. The lee Neck sizer is wonderful in the 300 Win.
Mikecr
Well-Known Member
Your donuts aren't caused by neck sizing.
Next prep of new brass, you can turn up onto shoulders a little bit & head this off for a while.
Should never re-turn necks(after fired). Best done with new out of box cases.
You should also be expanding necks with every neck sizing & this should help donut interference. And also you should know that seating bearing very near shoulder junction increases tension variance
Next prep of new brass, you can turn up onto shoulders a little bit & head this off for a while.
Should never re-turn necks(after fired). Best done with new out of box cases.
You should also be expanding necks with every neck sizing & this should help donut interference. And also you should know that seating bearing very near shoulder junction increases tension variance
