300 rum throat length

Discussion in 'Reloading' started by trapping, Mar 26, 2009.

  1. trapping

    trapping New Member

    Messages:
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    Joined:
    Nov 26, 2008
    Had a custom 300 rum built. The smith built it for handloads only and said if I wanted to shoot factory loads, they would have to cut the throat longer. Why would the smith cut the throat shorter than factory specs.
    Thanks
     
  2. woods

    woods Well-Known Member

    Messages:
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    Jun 4, 2006
    A couple of guesses

    1. He is giving you a tight chamber which will increase pressure and thus velocity

    2. He wanted to sell you an action that had a short magazine.

    I have a custom 338 RUM that was made from a 338 win mag and I had to have a short throat in order to fit the mag and reach the lands. One thing you will have to watch for is that you will develop pressure signs at a lower powder charge than one with a longer throat. So don't load close to max until you work up from way down.
     

  3. trapping

    trapping New Member

    Messages:
    2
    Joined:
    Nov 26, 2008
    Thanks woods. I supplied the action off of a brandnew 300 rum. I also thought he said that it won't be a velocity machine, but that the accuracy would be improved. He did mention to start on the bottom loads and work up.
     
  4. J E Custom

    J E Custom Well-Known Member

    Messages:
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    Jul 29, 2004
    I don't know why he would do that with out talking to you first but if it is short throated
    then you should not shoot factory ammo because it may be over max in your chamber.

    The only reason I can think of is if he had the reamer and was trying to save you money
    or you told him which bullet you were going to use and a short throat was nessary to
    work in the mag.

    You will not get the velocity with the short throat but it will allow you to seat the bullets
    close to the lands.

    If you want to shoot factory ammo then have him use a throating reamer and make it
    to within factory spect.

    J E CUSTOM