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Thread: Rear sight for non F-marked FSB

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  1. #1
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    Rear sight for non F-marked FSB

    So I just picked up a 14.5" Colt SOCOM barrel and it is not marked with an F. The brown truck o happiness has not gotten here yet.

    1) if it isn't marked, might it still be an F-height? How can I tell?

    2) if mounted on a flat-top upper, what would be an appropriate BUIS choice?

    3) Can I just replace the front sight post, or will it stick past the protective ears?

    Thanks

  2. #2
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    Quote Originally Posted by pubb View Post
    So I just picked up a 14.5" Colt SOCOM barrel and it is not marked with an F. The brown truck o happiness has not gotten here yet.

    1) if it isn't marked, might it still be an F-height? How can I tell?

    2) if mounted on a flat-top upper, what would be an appropriate BUIS choice?

    3) Can I just replace the front sight post, or will it stick past the protective ears?

    Thanks

    1) I don't know if they are all marked. The F marked sights are 0.04 taller. According to what I have seen the distance between the barrel to the flat surface between the ears of the FSB is 1.98 on the F marked and 1.94 on the standard.

    2) I have a sample of one upper with a non-F marked sight. I have a fixed Troy Battle Sight on it - works fine.

    3) If need be you could replace, several places have tall front sights: https://www.knsprecisioninc.com/prod...ht-040-taller/ (pricey) https://shop.windhamweaponry.com/products/9349056-mod This one is .030 taller: http://www.jsesurplus.com/midwestind...1-1-1-1-1.aspx (least expensive)

  3. #3
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    Colt doesn’t mark them with an F anymore if this barrel is less than a year old and is factory assembled.

    They are still the correct F height.

    You still need to use a military dimension rear sight.
    "Not every thing on Earth requires an aftermarket upgrade." demigod/markm

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    Quote Originally Posted by scottryan View Post
    Colt doesn’t mark them with an F anymore if this barrel is less than a year old and is factory assembled.
    Wonder why, wouldn't the F already be in the casting?

    In that case it seems like work/expense to remove it.

  5. #5
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    Quote Originally Posted by 26 Inf View Post
    Wonder why, wouldn't the F already be in the casting?

    In that case it seems like work/expense to remove it.

    The F is stamped in the forging after the forging is made. The same forging was used for F and non F front sight bases. The machining is what separates the two.

    Since colt no longer makes fixed handle rifles, they dropped the F stamping.
    "Not every thing on Earth requires an aftermarket upgrade." demigod/markm

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    Thanks!

  7. #7
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    Thanks for that information.

    Quote Originally Posted by scottryan View Post
    The F is stamped in the forging after the forging is made. The same forging was used for F and non F front sight bases. The machining is what separates the two.

    Since colt no longer makes fixed handle rifles, they dropped the F stamping.



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