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Bushmaster A1 help

Discussion in 'Black Rifle Forum' started by EOS, Dec 17, 2012.

  1. EOS


    May 30, 2012
    Central Kentucky
    I have been thinking about modernizing my Bushmaster xm15 e2s which is in the A1 configuriation. I was going to get a flat top upper reciever, (complete upper is out of my budget) along with MOE funiture, and possibly an Eotech 512. My question is will the gas block have to be removed to install the new reciever since the barrel must come out? I have heard the A1 gas blocks are attached differently and cant be removed without some gunsmithing. Is this build worth the time and money and possible headache? or should I trade it in and use the $800 build budget i have plus whatever i get for the old rifle and buy an M&P 15 flat top and modify it with whatever funds are left? Any of you knowledgeable AR guys out there I need some info here, having dealt with mainly handguns I am AR ignorant.
  2. mac66

    mac66 Huge Member Millennium Member

    Oct 28, 1999
    Blue Planet
    To pull the barrel off you just need to remove the hand guards, then disconnect the gas tube from the front sight base/gas block. It is removable by punching out the roll pin. You don't need to remove the front sight base/gas block unless you are using a free float hand guard. Remove the barrel with a barrel wrench and then re install it on your flat top upper. Replace the gas tube and you are good to go.
    Last edited: Dec 17, 2012

  3. zhix


    Jan 31, 2010
    I would try to keep Your current rifle and buy another gun. I don't think it would be worth it to change just the receiver itself.
    However, if $800 is the limit then sell it and add the cash to your budget, although I would think $800 could get a decent complete barreled upper, you could always wait and save up a bit more for the optic.
    Remember AR prices are likely to keep climbing in price...
  4. EOS


    May 30, 2012
    Central Kentucky
    thanks for the advice fellas, I have been going back and forth on what to do, between getting another Glock or M&P and saving some money or getting an arsenal AK or doing this build. but with what ever AWB may be looming, Id be sick if I spent 800 on a rifle I may have to bury in an undisclosed location. Hopefully they'll be a "grandfather" clause, but one must be prepared. I have a buddy that has the tools needed to do this build, Im just a little intimidated by working on a rifle that im not very familiar with.