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AR15 windage all the way to the left

mto7464mto7464 Member Posts: 60 ✭✭
edited November 2013 in Ask the Experts
A buddy of mine got a flat top upper and put a RRA NM carry handle on it. After sighting it in the rear site is all the way to the left leaving only about 2 min of windage. He sent the first one back and got this one and the same thing. I know nothing about these rifles but something is amiss. Just eyeballing it you can tell the rear sight is way left so it is not the carry handle. Any ideas?

Comments

  • rufe-snowrufe-snow Member Posts: 18,650 ✭✭✭
    edited November -1
    If it aint the handle or the rear sight, has to be the front sight. Being it was made as a flat top for optical sights. Perhaps the person who assembled the barrel & gas block didn't sweat the precise alignment. As much as would have been required, if it was specifically made for iron sights.



    EDIT #1,

    Here is a link to a black rifle site, that discusses this problem in great detail. And how to correct it. Apparently a lot of folks have had similar problems, after adding aftermarket iron sights.





    DELETED
  • charliemeyer007charliemeyer007 Member Posts: 6,572 ✭✭✭
    edited November -1
    If it still has (some) adjustment and shoots point of aim your are done. Maybe the barrel wasn't threaded in perfectly square.
  • andrewsw16andrewsw16 Member Posts: 10,728 ✭✭✭
    edited November -1
    I don't know what type of front sight you have, but if it is adjustable for windage, move it to the right. If it is not adjustable, it appears as if whoever mounted the barrel may have screwed it in too far. A smithy may be able to back it out a tiny bit, thus moving the front site over to the right. It won't take much. I actually had to do this to a Taurus revolver. There just wasn't enough range of motion in the rear sight to compensate for how far the barrel had been screwed in. A minor twist on the barrel to get it to center up fixed everything. Good luck. [:)]
  • TxsTxs Member Posts: 17,809 ✭✭✭
    edited November -1
    Seeing as you've tried two different rear sight assemblies and got precisely the same result, I'm in agreement that the barrel was improperly installed and causes the front sight base to list a shade to the right.

    Unless that barreled upper is warrantied your choices are to either reinstall the barrel correctly or just live with seeing your rear sight slammed to one side.

    If you're not equipped to do the work yourself, it shouldn't run much at all for a 'smith to accomplish.

    EDIT:

    quote:Originally posted by dcs shooters
    That's a problem with threaded barrels, BUT AR 15 barrels have a alignment pin and a separate nut [:0]
    My WAG is the gas block is not square with the upper receiver [^]
    I've seen some with quite a bit of slop in that pin engagement, especially if they're from different manufacturers - and that sounds to be the case here.

    I'd at least try and fix things by resetting the barrel instead of diving straight into the FSB, which is a much greater PITA. Loosen the barrel nut, insert a dowel through the FSB and maintain counterclockwise pressure while torquing it back down.
  • mto7464mto7464 Member Posts: 60 ✭✭
    edited November -1
    That is kind of the same conclusion we came to. I have installed M1 Garand barrels before and had to be careful to get the indexing correct.
  • dcs shootersdcs shooters Member Posts: 10,870 ✭✭✭
    edited November -1
    quote:Originally posted by charliemeyer007
    If it still has (some) adjustment and shoots point of aim your are done. Maybe the barrel wasn't threaded in perfectly square.


    That's a problem with threaded barrels, BUT AR 15 barrels have a alignment pin and a separate nut [:0]
    My WAG is the gas block is not square with the upper receiver [^]
  • sandwarriorsandwarrior Member Posts: 5,453 ✭✭✭
    edited November -1
    How are you guys coming up with 'realigning the barrel?' The barrel extension is clocked and torqued to the barrel. It has a pin on the front (rear actually) that mates with a slot cut in the upper. So, the barrel is not going to change angles in relation to the upper.

    One way to straighten this out is to realign the front sight. If you have the standard type front sight, there will be two grooves cut in the bottom of the barrel. Tapered pins are driven into those grooves through the front sight base. There is no changing that.

    As I see it, one way to fix this is to get an aftermarket gas block that does NOT have alignment pins. If you don't already have that. On this rail type gas block you will need to install your front sight. This is best done in a gun vise, or cleaning rack of some kind (like a Lead Sled). I use a varmint stand that I never take to the field any more. Whatever, something to hold the gun still while you bore sight it.

    The other option is to shim the side of the rear base to the side that is narrowest where it clamps to the picatinny rail on your upper.


    quote:Originally posted by MG1890
    quote:Originally posted by sandwarrior
    How are you guys coming up with 'realigning the barrel?' The barrel extension is clocked and torqued to the barrel. It has a pin on the front (rear actually) that mates with a slot cut in the upper. So, the barrel is not going to change angles in relation to the upper.

    One way to straighten this out is to realign the front sight. If you have the standard type front sight, there will be two grooves cut in the bottom of the barrel. Tapered pins are driven into those grooves through the front sight base. There is no changing that.

    As I see it, one way to fix this is to get an aftermarket gas block that does NOT have alignment pins. If you don't already have that. On this rail type gas block you will need to install your front sight. This is best done in a gun vise, or cleaning rack of some kind (like a Lead Sled). I use a varmint stand that I never take to the field any more. Whatever, something to hold the gun still while you bore sight it.

    The other option is to shim the side of the rear base to the side that is narrowest where it clamps to the picatinny rail on your upper.


    Easy. They are saying change the "clocking".


    NO. Because by changing the "clocking" you will be "un-torquing" the barrel extension. The barrel extension is torqued onto the barrel like a normal barrel is torqued onto a receiver. It's solid for all intents and purposes. It's not like a Savage where the barrel nut is torqued onto the receiver when headspace is arrived at.



    quote:Originally posted by dcs shooters
    NO, saying the front sight/ gasblock is not square with the receiver/crooked.


    ^^^^^^^
    This.

    Either the front sight base needs to be rotated into correct alignment with the upper receiver. Or, the rear sight needs to be aligned with the front sight.
  • MG1890MG1890 Member Posts: 4,460 ✭✭
    edited November -1
    quote:Originally posted by sandwarrior
    How are you guys coming up with 'realigning the barrel?' The barrel extension is clocked and torqued to the barrel. It has a pin on the front (rear actually) that mates with a slot cut in the upper. So, the barrel is not going to change angles in relation to the upper.

    One way to straighten this out is to realign the front sight. If you have the standard type front sight, there will be two grooves cut in the bottom of the barrel. Tapered pins are driven into those grooves through the front sight base. There is no changing that.

    As I see it, one way to fix this is to get an aftermarket gas block that does NOT have alignment pins. If you don't already have that. On this rail type gas block you will need to install your front sight. This is best done in a gun vise, or cleaning rack of some kind (like a Lead Sled). I use a varmint stand that I never take to the field any more. Whatever, something to hold the gun still while you bore sight it.

    The other option is to shim the side of the rear base to the side that is narrowest where it clamps to the picatinny rail on your upper.


    Easy. They are saying change the "clocking".
  • dcs shootersdcs shooters Member Posts: 10,870 ✭✭✭
    edited November -1
    NO, saying the front sight/ gasblock is not square with the receiver/crooked.
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