Expander mandrel and doughnuts

Discussion in 'Reloading Forum (All Calibers)' started by rhovee, Mar 4, 2018.

  1. rhovee

    rhovee

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    I have ran into some doughnuts on some necked down 270 WSM brass to 6.5 WSM brass. I use Redding bushing dies. Would using a .002-.003 smaller bushing than i am already using, then "push" the doughnut to the outside with an expander mandrel work? I already tried purchasing a Foster trimmer and inside neck reaming tool. Issue is that the tight neck chamber doesn't allow the neck to open up enough to only cut the doughnut. Looking for a way to figure this out for future projects....
     
  2. Dusty Stevens

    Dusty Stevens COVFEFE- Thread Derail Crew Gold $$ Contributor

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    The donut is best left alone. Its not hurting anything and when you try to cut it out you get broke off necks- that shuts you down in your tracks. As long as your freebore is correct you have nothing to worry about. If you have donuts before you ever shoot them just from necking down just run your expander in there right before you turn your necks and turn em normal.
     
  3. Lapua40X

    Lapua40X California Hunter Education Instructor Silver $$ Contributor

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    Reddng disagrees with you. From their web site: http://www.redding-reloading.com/tech-line-a-tips-faqs/147-advanced-case-forming-operations-

    "The "Donut"

    The second consideration is the formation of a "donut". This is a ring of thicker brass inside the neck of the newly formed case. The donut appears when the neck-shoulder junction of the newly formed case ends up closer to the base than the parent cartridge. This donut must be removed or dangerous pressures will result due to the lack of clearance for the case neck to release the bullet. Again, we recommend a minimum clearance of 0.003"."
     
  4. T-shooter

    T-shooter

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    The donut will push out much easier with your expander if you anneal the cases first.
     
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  5. Dusty Stevens

    Dusty Stevens COVFEFE- Thread Derail Crew Gold $$ Contributor

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    Like i said if you have the correct freebore it matters none. If youre shoving the bullet in past the neck then yes neck clearance may cause an issue.
     
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  6. mikecr

    mikecr

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    How did you size from 27cal to 26cal with a Redding bushing die?
     
  7. 243winxb

    243winxb

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    Size 6.5 WSM brass in a standard fl die. Expand. Outside neck turn to shoulder.

    My 243 bushing doesnt size all the way to the shoulder. It looks like a donut, but is not one.
     
  8. rhovee

    rhovee

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    I have a 270 wsm bushing die and a .293 bushing that necks it down. I was trying to avoid purchasing all the equipment for neck turning. Looks like I might have to. The doughnut is very apparent. On a fired case I have to push very hard against the wall to get the bullet to go past it.
     
  9. 243winxb

    243winxb

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    If your chamber has a true "tight neck" outside neck turning is a must do thing. The loaded round must have some clearence .
     
  10. Dusty Stevens

    Dusty Stevens COVFEFE- Thread Derail Crew Gold $$ Contributor

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    get your barrel throated longer
     
  11. 6MMsteve

    6MMsteve

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    what he said or use a collet die, trim your necks before you resize, and anneal them, I think
     
  12. Dusty Stevens

    Dusty Stevens COVFEFE- Thread Derail Crew Gold $$ Contributor

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    turkey pot pies.
     
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  13. Bart B.

    Bart B.

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    They say .003" clearance from case neck to chamber is needed.

    Does that refer to diameter difference?

    Or is that the clearance all the way around the case neck requiring a .006" diameter difference?

    It's interesting as their full bushing dies size case necks several thousandths short of case shoulders creating an external donut at that juncture. No chamber necks I know of are relieved there so internal donuts won't be formed as case necks may expand to chamber neck limits.

    Redding claims that external donut centers case necks in chamber necks in spite of it being smaller diameter than chamber necks.
     
  14. oldroper

    oldroper

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    If you have problem with Redding why don't you e-mail them instead of trying to play expert.
     
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