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colt's 1/7 twist

DocHolliday331DocHolliday331 Member Posts: 48 ✭✭
edited July 2002 in Ask the Experts
Im hearing a-lot of expert say that a 1/9 twist barrel is most appropriate for an AR typr rifle. And most of the makers (bush,olympic,rock(wilson), ALL use a 1/9. Why would colt use a 1/7?? Do they think its better? Is it cheaper? With colt's name I would'nt think that they'd put out an inferior product on purpose.
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Comments

  • 11echo11echo Member Posts: 1,007 ✭✭
    edited November -1
    I'm guessing this is an off-shoot from the military contracts. After Viet Nam, the military started running into "situations" where they needed to have the capacity to engage targets at longer ranges 300+. The twist rate you have talked about is acceptable for under 300 and lighter projectiles. Colt had to come up with a heavier projectile, and to do this had to increase the twist rate. My 2 cents ...Mark

    "FEAR the Goverment, that fears your ARMS"
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  • cpermdcpermd Member Posts: 5,273 ✭✭✭
    edited November -1
    One reason only.
    To stabilize that longassed M856 tracer round.
    cpermd
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  • DocHolliday331DocHolliday331 Member Posts: 48 ✭✭
    edited November -1
    thanks cpermd - so my next question would be - is this an inappropriate gun for me to buy since im only going to be using it for target shooting and home defense?
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  • leeblackmanleeblackman Member Posts: 5,303 ✭✭
    edited November -1
    CPERMD is 100% right. Thats the only reason. See back in the day the old M16's and AR15's had a 1 in 12" twist, this was great for the 55gr projectiles.

    The 1 in 7" is in MY OPINION what you'd want to do competition shooting if you reload, for use with 75gr A-Max bullet or something of a similar size.

    However the 1 in 9" is the perfect compromise between the 1in12 and the 1in7 twist. Gives you great capability for both light and heavy bullets. So it would be ideal for plinking, defense, ect. And my Colt has a 1in9" twist. They are available in 1in9", and probably more common in that. I find it really loves surplus SS109 ammo, and handles Black Hills 68gr BTHP moly bullets just fine.

    If I'm wrong please correct me, I won't be offended.

    The sound of a 12 gauge pump clears a house fatser than Rosie O eats a Big Mac !
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  • 11echo11echo Member Posts: 1,007 ✭✭
    edited November -1
    CPERMD Question if you will. ...WHY would Colt "worry" about trying to stabilize a projectile that is only used less than 20% of the time? Wouldn't they be more interested in trying to stabilize a projectile that the rifle was primarily intended to use the 62gr. ball ammo?
    I'm not saying the tracer ammo won't work with this twist rate Colt has come up with, but it seems to me Colt would be more interested dealing with the "common" round then a tracer. My 2 cents! ...Mark


    "FEAR the Goverment, that fears your ARMS"
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  • cpermdcpermd Member Posts: 5,273 ✭✭✭
    edited November -1
    M16 rifles had to shoot and stabilize anything shot through them for the military.
    I can say my 20th,29th and 30th rds were always tracers in the mags I loaded for myself.
    They hit within 8" at 400 yds of the M855 ball which was all I needed.
    Colt did exactly as they were told by the Army.
    cpermd
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  • leeblackmanleeblackman Member Posts: 5,303 ✭✭
    edited November -1
    Hey CPERMD, thanx for mentioning that. I really never thought of it. Its the perfect idea for keeping track of how low your magazine is without actually looking down it. I'm going to borrow that idea if ya don't mind, and start loading my mags like that.

    If I'm wrong please correct me, I won't be offended.

    The sound of a 12 gauge pump clears a house fatser than Rosie O eats a Big Mac !
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  • JustCJustC Member Posts: 16,056 ✭✭✭
    edited November -1
    didn't I hear that the military is going to 62gr projectiles? If so, then you would want the 1:7 twist, as the surplus ammo which will be available in several years, will be made for that twist. Just a thought, if I heard it right.



    A great rifle with a junk scope,....is junk.
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  • hecklerxkochhecklerxkoch Member Posts: 213 ✭✭✭
    edited November -1
    cperm is right I remember my drill sergeant saying somethiing like that when I asked him the same question. In boot camp some of our rifles weree different ie. 1-7 twist and 1-9 twist.

    New gun??? No, honey, I've had it for years.
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  • will270winwill270win Member Posts: 4,845
    edited November -1
    The 62 grain ball round with steel penetrator is already in use. We are still using the 55 grainer until depleted. The combat load Cpermd spoke of is what you should use in combat and the twist rate must stabilize it or you will adjust incorrectly in a fire fight. On a scale from 1 to bad, that would be very bad.


    ~Secret Select Society Of Suave Stylish Smoking Jackets~
    Will270win@nraonline.com
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