.308 subsonic rounds?? How do you do it????

Bullseyelr

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Does anyone have any info on how to make a .308 subsonic round to run through a CAN. I am using SMK BTHP 175 gr. for my regular loads w/ RL 15 powder and CCI BR-2 primers. Can I use the supplies that I already have or do I need different powder, bullets, primers???? Any help would be appreciated....Thanks
 

427Cobra

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  • Nov 24, 2005
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    Re: .308 subsonic rounds?? How do you do it????

    I use
    10 grains of Trailboss
    180 round nose
    215 mag primers
    Win or Lapua brass
     

    ggarrett1911

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    Re: .308 subsonic rounds?? How do you do it????

    Here's mine...

    10.2 gr Trailboss
    170 Hornady flat point
    CCI 300 large pistol primers
    Federal Gold Medal brass
     

    kombayotch

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    Sep 20, 2007
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    Re: .308 subsonic rounds?? How do you do it????

    8.0 gr. Titegroup
    180 Hornady RN
    WLR primer
    Lapua/Federal brass
    2.650" COAL

    Run a patch of oil down the bore and rub a little oil on each bullet. It will keep the velocities much more consistent. This will help with the Trailboss loads listed above as well.
     

    coldbeerchief

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    Re: .308 subsonic rounds?? How do you do it????

    What twist is your barrel??

    Subsonic 175 SMKs wobble badly out of my 11.25" twist Crusader.

    Hornady 180 RN shoot fine.

    LC LR brass
    Fed 215 mag primer
    10.2 Trailboss
     

    bohem

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    Re: .308 subsonic rounds?? How do you do it????

    The info on loads here is good, the caveat I would suggest also is (take the can off to try this first if you don't believe me)

    Seat the spire pointed boat tails backwards in the case. The CP and CM need to align differently at subsonic velocities for stability. This is why a 175 SMK wobbles but the 180 RN doesn't. It doesn't really have to do with bullet length, it has to do with shape.

    Even if your 1:10 twist will stabilize it up close I'm willing to bet that the boat tail first seating style will keep you stable well beyond what it does in "normal" configuration.

    If you use the round for hunting, it makes the thing less likely to deflect off a bone and just slam right through it too.