Dreaded Doughnut????????

Discussion in 'The Basics, Starting Out' started by Sako7STW, Mar 7, 2004.

  1. Sako7STW

    Sako7STW Well-Known Member

    Messages:
    433
    Joined:
    Feb 12, 2004
    Ok well I have decided to still give the k&M more of a shot today. In looking at the horrible instructions he talks about the "dreaded doughnut" What is this??? he states that you must adjust the screw on the expander to prevent this. My problem as I said is the screw is to short and it makes it a real pain to expand. So I am thinking just simply not use the screw and stop the press just prior to the neck mouth reaching the top of the mandral? Will that work?
     
  2. littletoes

    littletoes Well-Known Member

    Messages:
    362
    Joined:
    Apr 12, 2002
    Inside case necks, were the neck meets the shoulder, after several firings, reloadings, brass can develop a "doughnut".
     

  3. Boyd Heaton

    Boyd Heaton Well-Known Member

    Messages:
    1,071
    Joined:
    May 14, 2001
    I don't keck turn much brass.But I feel I will have this problem with my new 6.5 Heaton...I always thought doughnuts were for eating [​IMG]
     
  4. Varmint Hunter

    Varmint Hunter Well-Known Member

    Messages:
    2,522
    Joined:
    Dec 26, 2001
    Are doughnuts caused but firing or by pulling the expander button up through the neck?

    All of my brass is neck turned before firing and I do not use neck expanders;is this why I have never noticed the dreaded doughnuts that I've read so much about?

    Or is it possible that my doughnuts are more like munchkins and I didn't even see them? [​IMG]

    VH
     
  5. Boyd Heaton

    Boyd Heaton Well-Known Member

    Messages:
    1,071
    Joined:
    May 14, 2001
    <BLOCKQUOTE><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><HR>Are doughnuts caused but firing or by pulling the expander button up through the neck? <HR></BLOCKQUOTE>Good question...If you find out could you fill me in. [​IMG]
     
  6. Sako7STW

    Sako7STW Well-Known Member

    Messages:
    433
    Joined:
    Feb 12, 2004
    I plan to call them tomorrow, maybe he can fill me in in more detail. I am also going to see what he can do to make this expanding a little easier. I will let you know what I find out.
     
  7. Sako7STW

    Sako7STW Well-Known Member

    Messages:
    433
    Joined:
    Feb 12, 2004
    Well I just got off the phone with Ken from K&M. Basically he said all I need to do is just run the case over the expander just short of hitting it on the die. Easy enough. He said what you need to watch for is after you size your brass but not expand it, look into the neck. If you see a usually non uniform bulge starting in the neck, just in front of the shoulder then you should only expand to the point just short of the "doughnut". Then cut it out with the reamer. if you run the doughnut over an expander it will just smash the doughnut down and force the material back into the shoulder area. What this causes is an uneven thickness of your shoulder. So it's better to cut out the doughnut to keep things even.

    What the cause of the doughnut is the brass flowing forward from the shoulder area into the neck area. He said I will probably never have the doughnut problem as i dont get that many shots out of my brass before I can them on my STW, maybe on my .243 though.

    I hope this made sense, I am not that great at explaining details.

    [ 03-08-2004: Message edited by: Sako7STW ]
     
  8. BountyHunter

    BountyHunter Writers Guild

    Messages:
    4,803
    Joined:
    Jun 13, 2007
    Sako7stw

    also understand you can cut down onto the shoulder and thin it out. This gives the brass a place to flow and fill up rather than come into the neck.

    I always cut a little ways down onto the shoulder. Makes sure no donuts coming into the neck. the KM tool is great, but works best off a power screwdriver instead of hand held. Much cleaner and smoother cut.

    BH
     
  9. Varmint Hunter

    Varmint Hunter Well-Known Member

    Messages:
    2,522
    Joined:
    Dec 26, 2001
    Sako,

    If you were able to see the doughnut, couldn't you just run the case through a sizing die and let the expander button swage the doughnut to the outside of the neck where it could easily be turner off?

    VH

    [ 03-08-2004: Message edited by: Varmint Hunter ]