Having pressure problems with 6mm ackley

Discussion in 'Reloading' started by Idaho Trecker, Aug 30, 2013.

  1. Idaho Trecker

    Idaho Trecker Well-Known Member

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    Apr 19, 2013
    I have a 6mm ackley with a 22.5" barrel and am having pressure problems when reaching the max loads listed for a standard 6mm. I am shooting 95 Berger VLD's and have them .003 off the lands. I was wondering if anyone has any ideas why I am having this problem. I have the just enough headspace so the bolt closes with the slightest resistance. I am having primers flatten and slightly crater. I am using IMR 4831 and H 414. With the 414 I have only gone to 45 grains and have pressure problems. Anyone have any suggestions???
     
  2. bullfrog

    bullfrog Well-Known Member

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    Jul 27, 2010
    I have had a batch of H414 that had a much faster burn rate than the reloading manual suggested. I loaded a middle of the road charge in the manual for a 220 swift and my velocity was about 250 fps too high and I had to beat open the bolt. I have had other batches of H414 that were dead on what the manual said. Did you chronograph your loads to see if the velocities are what you're expecting?
     

  3. Idaho Trecker

    Idaho Trecker Well-Known Member

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    Apr 19, 2013
    I did chrono the loads and that was also disappointing. I was getting 3285 average and a friend was shooting a standard 243 win with the same length barrel and 95 Berger Classic averaging 3300. I have also had the same problem shooting IMR 4831 where the velocities are low and pressures seem high. I'm not getting the extra velocity that I should with the ackley. Thanks for the input