"Super-sonic" question...

Discussion in 'Rifles, Bullets, Barrels & Ballistics' started by JonathanLarson, Jan 4, 2005.

  1. JonathanLarson

    JonathanLarson Active Member

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    \"Super-sonic\" question...

    Hey Guys,

    Will a silencer quiet down a super-sonic crack? Does it work at all when the bullet goes super-sonic?

    Thanks
     
  2. kregg

    kregg Member

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    Re: \"Super-sonic\" question...

    silencer's only work if your bullet is sub-sonic.
     

  3. Guest

    Guest Guest

    Re: \"Super-sonic\" question...

    It will drop the noise level a bunch but if the bullet is still comming out faster than 1100fps its gonna have a crack to it , I have a 308 with a silencer , it sounds about like a 22LR with regular loads.
     
  4. jb1000br

    jb1000br Well-Known Member

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    Re: \"Super-sonic\" question...

    they WORK with any ammo, but the "hollywood" quiet doesnt happen till you put sub ammo thru it--stick with 1050 or lower--I have had a crack at 1090fps.

    I shoot my 223 with it all the time with 50gn vmax at 3500fps--I love it!! can shoot w/o ear protection no problem--i agree--sound like 22RF.

    the 308, i would compare to a stinger 22LR

    YMMV,
    JB
     
  5. brian b

    brian b Well-Known Member

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    Re: \"Super-sonic\" question...

    I tinkered around with this a couple years ago making my own silencer (yes I know it is illegal ) I found out by experimenting that atleast with the technology I had if a bullet goes supersonic a silencer is useless, if you keep the bullet subsonic my highly modified Kawasaki KX500 muffler worked like a charm.(a bit heavy though)
    B
     
  6. Dave King

    Dave King Well-Known Member

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    Re: \"Super-sonic\" question...

    I believe you'll be happier calling them "suppressors" rather than "silencers".

    They suppress the noise associated with the expanding gases used to push the bullet from the bore. They DO NOT suppress the sounds made by the projectile.

    The super-sonic "crack" is a projectile related sound/event. The projectile is beyond the confines of the barrel and suppressor when the "crack" sound is made so there's no way for the suppressor to do anything for this type sound.

    Suppressor "suppress" the muzzle blast sound signature, muzzle flash, dust/debris signature and reduce recoil. They also get HOT and create mirage problems when used in sustained fire situations.

    If you fire sub-sonic ammunition and have a quality suppressor the critter you are shooting (or shooting at) will be able to hear the round coming (and if you miss) will also be able to hear the round going past and beyond. This is because the projectile is traveling slower than the speed of sound allowing the "whoosh" sound of the disturbed air to arrive before the projectile. After a little practice people can often easily identify the direction of the source of the incoming projectiles when sub-sonic ammunition is used. When the rounds are super-sonic the "crack" is made by the pressure wave pushed by the projectile will be heard as if it came from about 90 degrees to the source of the projectile. The target will not be able to hear the round come or go, it will be able to hear the secondary "cracks" as the projectile passed obstructions along it's flight path and the impact sound. The projectile impact sound at it hits the intended target or anything else is of varying intensity and can be quite loud...we often hear this same sound when shooting once the distance (time of flight) is sufficient for the two sound events to be differentiated by our ears.

    They're suppressors, not silencers.
     
  7. jb1000br

    jb1000br Well-Known Member

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    Re: \"Super-sonic\" question...

    So what dave is trying to say is :

    THEY ARE NOT USELESS WITH SUPERSONIC AMMO!!!! /ubbthreads/images/graemlins/laugh.gif

    Sorry for that dave /ubbthreads/images/graemlins/wink.gif

    They are quite a relief when using full-house ammo in the field.

    BTW--they reduce recoil as well /ubbthreads/images/graemlins/wink.gif

    JB
     
  8. daveosok

    daveosok Guest

    Re: \"Super-sonic\" question...

    Dave
    Do you have any load data for subsonic loads in any calibers?
    Thanks
     
  9. JonathanLarson

    JonathanLarson Active Member

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    Re: \"Super-sonic\" question...

    Thanks guys...
     
  10. Dave King

    Dave King Well-Known Member

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    Re: \"Super-sonic\" question...

    Yes, I have a few loads for 308 Win but they are not for general use. They're position sensitive as I don't/didn't use a filler in the case and couldn't use a giant long projectile (I use a Speer 125 TNT vice a 240 Sierra MK). Using a filler can be a problem as it'll eventually get caught up in the baffles of the suppressor and you'll end up with a baffle strike by a projectile (not a good thing). I used a very small amount of power and carried the rifle upright to keep the powder seated next to the primer until a shot was required...change the position a bit and the powder burn/ingition rate changed a bit and the rounds were supersonic (not what I desired).
     
  11. jb1000br

    jb1000br Well-Known Member

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    Re: \"Super-sonic\" question...

    [ QUOTE ]
    Yes, I have a few loads for 308 Win but they are not for general use. They're position sensitive as I don't/didn't use a filler in the case and couldn't use a giant long projectile (I use a Speer 125 TNT vice a 240 Sierra MK). Using a filler can be a problem as it'll eventually get caught up in the baffles of the suppressor and you'll end up with a baffle strike by a projectile (not a good thing). I used a very small amount of power and carried the rifle upright to keep the powder seated next to the primer until a shot was required...change the position a bit and the powder burn/ingition rate changed a bit and the rounds were supersonic (not what I desired).

    [/ QUOTE ]


    Dave, my load with n320 and LP primers and 150gn lead bullets didnt seem too position sensitive, even though i tested it fore and aft--seemed about 80fps spread IIRC. Gotta watch how close you play to the sound barrier /ubbthreads/images/graemlins/smile.gif

    I gave up squib loads in my 223 and just shoot normal ammo thru it /ubbthreads/images/graemlins/wink.gif

    JB
     
  12. brian b

    brian b Well-Known Member

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    Re: \"Super-sonic\" question...

    Dave ,
    Excellent explanation I stand corrected supressor not silencer, allthough my supressor was made from a silencer
    just one of those things that get you tounge twisted.
    B