Page 2 of 4 FirstFirst 1234 LastLast
Results 11 to 20 of 40

Thread: Is this normal??????!!!!!!

  1. #11
    Join Date
    Jun 2007
    Location
    WA
    Posts
    454
    Feedback Score
    5 (100%)
    Um....how does the top rail of the handguard align with the rail of the upper receiver?

    If that's off, then that means your handguard is the culprit.

    If that isn't off, use your calibrated eyeball to see if the rail bends or twists the further it goes out from the reciever towards the front sight.

    If it doesn't, then you are correct that your FSB/barrel (most likely the entire barrel) is slightly canted.

    If it is the FSB and not the entire barrel, It probably relates (as I-Gunz noted) to your install of the FSB. How far in have you driven the FSB pins?

    I'll re-state, do NOT start smacking the shit out of your rifle until you have gone through the above checks and then, all of that being good, taken the damn thing to the range and shot it first.


    p.s. did you re-torque on your barel nut during the install process?
    Last edited by GrumpyM4; 05-01-12 at 02:55.
    It is missing the point to think that the martial art is solely in cutting a man down; it is in killing evil. It is in the strategem of killing the evil of one man and giving life to ten thousand -Yagyu Munemori

  2. #12
    Join Date
    May 2009
    Posts
    145
    Feedback Score
    18 (100%)
    Did you use something to bridge the rail (like a carry handle) before tightening down the rail bolts?

    To check if fsb is canted, take everything off (i.e rail, optics) eyeball down the upper rail at the FSB. You can get an idea if FSB is straight.

    If the FSB is in fact canted, and it really bothers you... Install a low pro gas block and get an 11" rail to float right over. This way you can install flip up back up irons and have a clean sight picture when using optics.

  3. #13
    Join Date
    Mar 2011
    Posts
    1,542
    Feedback Score
    1 (100%)
    It looks like the rail is a little off. Look how the optic and the FSB line up, then look at the rail. The rail looks turned slightly to the right.

  4. #14
    Join Date
    Apr 2009
    Location
    Wisconsin
    Posts
    2,908
    Feedback Score
    8 (100%)
    Quote Originally Posted by SPM14430 View Post
    Did you use something to bridge the rail (like a carry handle) before tightening down the rail bolts?

    To check if fsb is canted, take everything off (i.e rail, optics) eyeball down the upper rail at the FSB. You can get an idea if FSB is straight.

    If the FSB is in fact canted, and it really bothers you... Install a low pro gas block and get an 11" rail to float right over. This way you can install flip up back up irons and have a clean sight picture when using optics.
    Or if it impedes function, the OP could send it back to the manufacturer.
    FSB > flip up BUIS
    Quote Originally Posted by scottryan View Post
    Anybody that owns or sells pistol versions of assault rifles is a bottom feeder, irregardless of the ban status of certain ammunition.

    They are illigetimate weapons that have no real purpose other than to attract retards to the gun community.

  5. #15
    Join Date
    Nov 2010
    Posts
    380
    Feedback Score
    5 (100%)
    Quote Originally Posted by polymorpheous View Post
    FSB > flip up BUIS
    X2... No reason not to have one unless its a precision build

  6. #16
    Join Date
    May 2006
    Location
    VA/OH
    Posts
    29,630
    Feedback Score
    33 (100%)
    Quote Originally Posted by CLJ94104 View Post
    Just came across this thread. https://www.m4carbine.net/showthread.php?t=18088 Grant says hitting the FSB wa rubber mallet may solve my slight misalignment issue. Do you gentlemen agree?
    LOL. First, shoot the gun and verify what is going on. Then, it if it too far out, have the FSB re-installed by someone that knows what they are doing.



    C4

  7. #17
    Join Date
    Jan 2012
    Location
    Tampa, FL
    Posts
    363
    Feedback Score
    3 (100%)
    I have not re torqued the barrel nut. All I did was cut off the delta ring, spring, etc, and then removed the FSB pins and slid the FSB forward just slightly to cut off hand guard cap. Then slid it back into place and knocked the pins in all the way. I just re-aligned the rail (it was a little bit off to the right, I used the carry handle as a bridge during install and its perfect now) and the FSB still seems SLIGHTLY canted left. I tried to go to the range this morning but they're closed, gotta wait until tomorrow. Hopefully it doesn't impair function (I don't think it will)

  8. #18
    Join Date
    May 2006
    Location
    VA/OH
    Posts
    29,630
    Feedback Score
    33 (100%)
    Quote Originally Posted by CLJ94104 View Post
    I have not re torqued the barrel nut. All I did was cut off the delta ring, spring, etc, and then removed the FSB pins and slid the FSB forward just slightly to cut off hand guard cap. Then slid it back into place and knocked the pins in all the way. I just re-aligned the rail (it was a little bit off to the right, I used the carry handle as a bridge during install and its perfect now) and the FSB still seems SLIGHTLY canted left. I tried to go to the range this morning but they're closed, gotta wait until tomorrow. Hopefully it doesn't impair function (I don't think it will)
    I have never installed this rail (yet), but isn't one of the things going for it is that you do NOT have remove the FSB???




    C4

  9. #19
    Join Date
    Apr 2009
    Location
    Wisconsin
    Posts
    2,908
    Feedback Score
    8 (100%)
    Quote Originally Posted by C4IGrant View Post
    I have never installed this rail (yet), but isn't one of the things going for it is that you do NOT have remove the FSB???




    C4
    Correct.
    The FSB does not have to come off to install this rail.
    Quote Originally Posted by scottryan View Post
    Anybody that owns or sells pistol versions of assault rifles is a bottom feeder, irregardless of the ban status of certain ammunition.

    They are illigetimate weapons that have no real purpose other than to attract retards to the gun community.

  10. #20
    Join Date
    May 2006
    Location
    VA/OH
    Posts
    29,630
    Feedback Score
    33 (100%)
    Quote Originally Posted by polymorpheous View Post
    Correct.
    The FSB does not have to come off to install this rail.
    Thought so. Since the FSB can be a PITA to remove and to re-install properly (as the OP found out), why remove it if the rail doesn't require it???

    If one was going to go through all this trouble, then why not buy a one piece, free floating rail???????



    C4
    Last edited by C4IGrant; 05-01-12 at 11:38.

Page 2 of 4 FirstFirst 1234 LastLast

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •