Page 1 of 4 123 ... LastLast
Results 1 to 10 of 32

Thread: Witness marks in upper from BCG cam pin

  1. #1
    Join Date
    Nov 2007
    Location
    Miami, FL
    Posts
    567
    Feedback Score
    0

    Witness marks in upper from BCG cam pin

    Is this typical?

    I just noticed so I checked my RRA NMA2 that I've fired 10x as many rounds thru and it is there as well though much less obvious.

    About 200 rounds









    Last edited by danpass; 08-15-13 at 22:19.
    Dan Miami, FL

  2. #2
    Join Date
    Apr 2012
    Location
    MN
    Posts
    97
    Feedback Score
    2 (100%)
    Yes it's completely normal.
    Quote Originally Posted by 308sako View Post
    But I must advise that trigger time will do more than shopping time.

  3. #3
    Join Date
    Nov 2007
    Location
    Miami, FL
    Posts
    567
    Feedback Score
    0
    Hmmm …… well ok.

    I just wonder why have this cutout in the upper for the cam pin if it is going to strike anyway ……

    Cutout centered too far forward?
    Last edited by danpass; 08-15-13 at 23:06.
    Dan Miami, FL

  4. #4
    Join Date
    Mar 2012
    Location
    PA
    Posts
    649
    Feedback Score
    16 (100%)
    It's settling in. Getting comfy.


    "It's Dangerous To Go Alone! Take This."

    https://www.facebook.com/Blak1508
    Instagram Blak1508

  5. #5
    Join Date
    Jan 2008
    Location
    AZ-Waging jihad against crappy AR's.
    Posts
    24,900
    Feedback Score
    104 (100%)
    What is your experience level with the AR15 FOW?



    Owner/Instructor at Semper Paratus Arms

    Facebook: https://www.facebook.com/SemperParatusArms/

    Semper Paratus Arms AR15 Armorer Course http://www.semperparatusarms.com/cou...-registration/

    M4C Misc. Training and Course Announcements- http://www.m4carbine.net/forumdisplay.php?f=141

    Master Armorer/R&D at SIONICS Weapon Systems- http://sionicsweaponsystems.com

  6. #6
    Join Date
    Nov 2007
    Location
    Miami, FL
    Posts
    567
    Feedback Score
    0
    Just this and my A2. Self researched.

    This one I built.

    (As far as lube, I had wiped the area to get a better pic)

    I had gone thru your single post on Inspection
    Dan Miami, FL

  7. #7
    Join Date
    Jan 2008
    Location
    AZ-Waging jihad against crappy AR's.
    Posts
    24,900
    Feedback Score
    104 (100%)
    I am asking because this is in fact fairly normal.

    Quote Originally Posted by danpass View Post
    Just this and my A2. Self researched.

    This one I built.

    (As far as lube, I had wiped the area to get a better pic)

    I had gone thru your single post on Inspection



    Owner/Instructor at Semper Paratus Arms

    Facebook: https://www.facebook.com/SemperParatusArms/

    Semper Paratus Arms AR15 Armorer Course http://www.semperparatusarms.com/cou...-registration/

    M4C Misc. Training and Course Announcements- http://www.m4carbine.net/forumdisplay.php?f=141

    Master Armorer/R&D at SIONICS Weapon Systems- http://sionicsweaponsystems.com

  8. #8
    Join Date
    May 2011
    Posts
    3,095
    Feedback Score
    7 (89%)
    Normal, it will get to a point and stop. The big cutout is because the cam pin needs a place to go when the BCG is in battery as it cams to the side when the bolt locks in place.
    Quote Originally Posted by C4IGrant View Post
    Colt builds War Horses, not show ponies.
    Quote Originally Posted by Iraqgunz View Post
    This is 2012. The world is going to end this December and people are still trying to debate the merits of piece of shit, cost cutting crap AR's. Really?

  9. #9
    Join Date
    Nov 2010
    Location
    MI
    Posts
    3,516
    Feedback Score
    22 (100%)
    Here is a good discussion related to cam pins

    Cam-pin wear as a contributor to bolt failure?

    https://www.m4carbine.net/showthread.php?t=134117
    Last edited by Clint; 08-16-13 at 09:03.
    Black River Tactical
    BRT OPTIMUM Hammer Forged Chrome Lined Barrels - 11.5", 12.5", 14.5", 16"
    BRT EZTUNE Preset Gas Tubes - PISTOL, CAR, MID, RIFLE
    BRT Bolt Carrier Groups M4A1, M16 CHROME
    BRT Covert Comps 5.56, 6X, 7.62

  10. #10
    Join Date
    May 2011
    Posts
    3,095
    Feedback Score
    7 (89%)
    Quote Originally Posted by Clint View Post
    Here is a good discussion related to cam pins

    Cam-pin wear as a contributor to bolt failure?

    https://www.m4carbine.net/showthread.php?t=134117
    Good bolts break lugs generally before failing at the cam pin slot.
    Quote Originally Posted by C4IGrant View Post
    Colt builds War Horses, not show ponies.
    Quote Originally Posted by Iraqgunz View Post
    This is 2012. The world is going to end this December and people are still trying to debate the merits of piece of shit, cost cutting crap AR's. Really?

Page 1 of 4 123 ... 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
  •