AR-15 Barrel Markings

Discussion in 'Technical Questions & Information' started by CountryGunsmith, Feb 23, 2003.

  1. CountryGunsmith

    CountryGunsmith New Member

    Joined:
    Jan 29, 2003
    Messages:
    5,115
    Location:
    Deep Piney Woods of East Texas
    Moskovskyya
    Member
    Posts: 22
    (12/23/01 8:13:03 pm)
    Reply | Edit | Del All AR black rifle question
    --------------------------------------------------------------------------------
    I have an AR rifle with barrel markings C MP 5.56 NATO 1/7.
    does anyone know what the "MP" means?

    Thanks

    Tac401
    Administrator
    Posts: 3092
    (12/23/01 9:40:14 pm)
    Reply | Edit | Del
    ezSupporter
    Re: AR black rifle question
    --------------------------------------------------------------------------------
    Mosk,

    All Colt barrels are marked that way, I don't remember
    the meaning of the MP but the NATO 1/7 means 1-turn
    in 7-inches regarding rifling in the barrel, the 1-in-7 is
    the nato standard for using the current issue 62-grain
    steel core bullet, most commercial AR's now come with
    a 1/9 barrel for more bullet stablization and to effectively
    fire most any .223 weight bullets.

    I'm sure someone will be here to give you the meaning
    of the MP and jar my memory lol!
    The Firearms Forum Vietnam Memories Bulletin Board Contact Administrator

    M4A3
    Member
    Posts: 1
    (1/16/02 9:19:36 pm)
    Reply | Edit | Del Re: AR black rifle question
    --------------------------------------------------------------------------------
    MP stands for 'Magnetic Particle' non-destructive testing...for more detail on "black Rifle" stamping ID see the below:

    www.biggerhammer.net





    Edited by: bondai at: 1/16/02 11:28:27 pm
Similar Threads
Forum Title Date
Technical Questions & Information AR-15 Barrel? chrome or not? Sep 4, 2012
Technical Questions & Information Hard AR-15 Question - Chrome Lined Barrel or Not? Jul 27, 2011
Technical Questions & Information How to remove melted plastic/nylon from an AR-15 barrel? Jan 3, 2009
Technical Questions & Information 80% lower AR-15 question Mar 6, 2014
Technical Questions & Information Magpul Accessories for AR-15??? Mar 30, 2013

Share This Page