Unstable bullets in 300 blackout

Discussion in 'Ammunition & Reloading' started by 45 for me, Jul 16, 2016.

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  1. 45 for me

    45 for me
    Oregon
    Well-Known Member

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    I have a Liberty Leonidas 300bk upper. It's an 8 1/2" Lilja barrel with a large integral suppressor. 1/8 twist

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    I am shooting Missouri bullet companies lead, polymer coated, 245gr bullets

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    I have shot several hundred of these so far with no issues, but I noticed after doing a rapid fire on an already warm firearm, some of the bullet strikes were horizontal at 20yds. That wasn't happening during slow fire, and I have shot accurately with these loads at 100yds.

    The load is 12gr with accurate 1680. These are right at the 1000-1050fps range.

    Thoughts?
     
  2. Twodogs

    Twodogs
    portland Or
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    I would drop down to a 200-208 gr bullet or try leatherhead 245's they are sized to .311 and are said to do better then the Missouri bullets at .309.
    I'm shooting a 1-7" and have better luck with 180-200 gr bullets.
     
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  3. 45 for me

    45 for me
    Oregon
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    I am going to check the barrel for lead fouling too. Do you think hot barrel & lead bullet combo could cause this? The weird thing is they seemed to be stable with slow fire.

    Thanks for the tip on Leatherhead.
     
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  4. Twodogs

    Twodogs
    portland Or
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    Wouldn't hurt to give the barrel a real good cleaning and shoot some slow 3 shot groups.
     
  5. Camelfilter

    Camelfilter
    Salem
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    ?Polymer melting/melting too soon under rapid?
     
  6. PaulB47

    PaulB47
    Hillsboro
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    Verify your velocity after getting things heated up? Should be the same but who knows...

    I agree too with looking at a larger diameter. Maybe harder too?
     

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