300 WSM Head Space?

Discussion in 'Reloading' started by Rickyrebar, Mar 18, 2010.

  1. Rickyrebar

    Rickyrebar Active Member

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    New to reloading... I am reloading once fired 300 WSM cases.
    I full resized a dozen or so a few weeks ago and found that when chambered the bolt closed hard. I posted my problem here and had several responses suggesting that my die was not set up correctly or possibly needing to have the head space of my rifle measured. As it turned, out after visiting with a local gunsmith, I did not have my die adjusted correctly. It needed to be cranked down into the press more. As suggested by the gunsmith, he instructed me to set up the die per manufactures instructions, resize a case then chamber the round, if the bolt would still not close, readjust the die (small increments at a time) and resize... doing this until the case would chamber without resistance while closing the bolt.
    So I have the die set now to resize a case that will physically work.
    Is this good enough or do I need to be concerned with the "head" to "shoulder" dimension? I would assume that if the case was resized just to the point to where the bolt closes, I would not have under sized it to the point to where there is too much head space?
    I have calipers, so I can measure the overall case length, but I do not have any accurate way to measure the distance from the head to the shoulder.
    I see Hornaday makes a device that attaches to a caliper that will measure that dimension.
    Am I splitting hairs here or?
     
  2. retiredcpo

    retiredcpo Well-Known Member

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    Rickey
    I am by no means a expert not even close
    But had the same problem with my 300WSM
    I ended up completely lowering the hadle on the press and screwing the die down untill it touched the 1/4 turn more
    everyhting has been fine since I have 4 or 5 loadings on my brass and no problems
    I would say do like you are but keep and eye on your brass.
    some guys have problems from over working the brass.
    Retiredcpo
     

  3. Long Time Long Ranger

    Long Time Long Ranger Well-Known Member

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    The 300 wsm headspaces off the shoulder so for best accuracy you want it touching firm but not hard to close the bolt. Sounds like you have it just about right now. I fireform mine then neck size only so I get that perfect headspace fit off the shoulder.
     
  4. Rickyrebar

    Rickyrebar Active Member

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    Long Time Ranger,
    When you neck resize, are you using a special die that only resizes the neck, or can this be done with a full length die as well?
    From the reading I have done, I would like to neck size my stuff but have read that rounds reloaded for hunting, should be full resized. I assume it is to assure that the ammo will feed into the chamber smoothly.
     
  5. royinidaho

    royinidaho Writers Guild

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    To neck size I use the FL sizing die and come down the neck half way.

    Back before you were born, sizing the neck 1 caliber was recommended.
     
  6. Long Time Long Ranger

    Long Time Long Ranger Well-Known Member

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    Most manuals recomend you full length size for the reason you stated. I have a redding 300 wsm FL die. I use it to neck size only and when they get to tight after a few firings I set it to push the shoulder back a little and away I go again. This can be done with most any FL die. Directions should come with the die for neck sizing. I have not had the problem you and retiredcpo had. I also use the hornady generic neck sizers for each caliber. I have all kinds of wildcat cartridges and instead of getting a die for each one I just neck size with the hornady die. Saves a lot of money. I neck size only with all my rifles hunting or targets.
     
  7. Rickyrebar

    Rickyrebar Active Member

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    Royinidaho,

    "To neck size I use the FL sizing die and come down the neck half way."

    Forgive my inexperience here, but, I am trying to imagine how to set the die up to only come down the neck "half way"... per RCBS instructions, setting the die up to FL resize, it is run down to contact shell holder + 1/4 +/- turn... so, to neck size, the die would not even contact the shell holder? And, the primer punch would still knock out the spent primer?
    I guess there is an adjustment on the primer punch. They say to adjust it to extend below the bottom of the die 3/16" (I think), so would this dimension have to be increased to punch the primer while the case is only 1/2 of the way into the die?
    Am I on the right track?
     
  8. Long Time Long Ranger

    Long Time Long Ranger Well-Known Member

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    Adjust the primer punch by turning the adjustment on top of the die to your desired setting. To neck size screw the die down a little at a time while veiwing the neck after each try. You can see where the die stopped sizing each time by finding the ring on the neck left by the lubricant. Keep bringing the die down until that ring is as close to the shoulder without touching it as you can get. Now you are perfectly neck sized.
     
  9. Rickyrebar

    Rickyrebar Active Member

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    When neck sizing, I have read that eventually you have to FL.
    What indicators are you looking for to determine when to go with FL?
    Also, I have seen the term "bumping the shoulder back" used on several forums, is this slang for FL resizing or is it another process of partially sizing the case?
     
  10. royinidaho

    royinidaho Writers Guild

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    The primer pin needs to "just" extract the primer. Caution: do not let the expander touch the case head. That's when you will feel the ram "stop" and are apt to bend things.

    With the ram at the top of the stroke, screw down the die until it touches the case.
    Leave the primer punch where it is or, remove it.
    Screw the die down a little, smaller increments lets you get an idea for how much a complete turn is worth.
    Run the ram w/cartridge to the top.
    Note how much of the neck is sized.
    Repeat until you are size the amount of the neck that you desire. (~1/2) for an '06 length neck. Maybe a little more for a short necked case (264 Win as an example).

    I like to resize enough that the base of die at least touches the body of the case and the top of the stroke. The intent is to maintain center alignment. However, I don't think it works as the neck is already sized 'before' the die base touches brass.:rolleyes:

    Also I let my expander ball/primer extractor rod float. That is I don't tighten the the lock nut at the top of the die. Caution: too much float and primer ejector pins start getting bent.

    Finally, adjust the expander ball and primer pin to "just" extract the primer.

    Notes: If reloading to reasonable pressures the shoulder bump (ram all the way to the die base) every so many loads will be sufficient.

    If you run 'max' pressures the case just above the base will require resizing every time. Thus a FL resize is in order every time.

    Probably TMI but hope it helps. Your post suggests that you are headed in the right direction.

    HTH
     
  11. etisll40

    etisll40 Well-Known Member

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    ftt