Page 2 of 4 FirstFirst 1234 LastLast
Results 11 to 20 of 31

Thread: Downsides of a Non-Shrouded Firing Pin?

  1. #11
    Join Date
    Jan 2008
    Location
    Cincinnati, OH
    Posts
    36
    Feedback Score
    0
    I'm sorry, this is a bit of an apples to oranges compairison. The OP's gun is a Colt. Mine is a used Franken gun.
    When I bought it, it was 16" HBAR A3. The lower is Bushmaster. It does not have a sear block.
    The upper is of undetermined origin. 3 local 'smiths and a police trainer that I recently showed it to say they don't think its the origional upper. the upper is black in color while the lower is gray. Not being a "fit and finish" guy, I didn't realize this meant anything. The reciever has no marks any of us could see. The barrel was also unmarked except for the "Wilson Combat" on the bottom of the muzzle break. But who knows when that was added. Now its a 14.5 + Phantom lightweight (thanks ADCO).

    ETA: By "won't run", I mean it persistantly short strokes. Not every round but several per magazine. It runs like a sewing machine with the origional BCG.
    Last edited by Tweightwee; 07-03-09 at 22:00. Reason: incomplete answer.

  2. #12
    Join Date
    Oct 2008
    Location
    oregon
    Posts
    7,126
    Feedback Score
    7 (100%)
    Quote Originally Posted by Tweightwee View Post
    I'm sorry, this is a bit of an apples to oranges compairison. The OP's gun is a Colt. Mine is a used Franken gun.
    When I bought it, it was 16" HBAR A3. The lower is Bushmaster. It does not have a sear block.
    The upper is of undetermined origin. 3 local 'smiths and a police trainer that I recently showed it to say they don't think its the origional upper. the upper is black in color while the lower is gray. Not being a "fit and finish" guy, I didn't realize this meant anything. The reciever has no marks any of us could see. The barrel was also unmarked except for the "Wilson Combat" on the bottom of the muzzle break. But who knows when that was added. Now its a 14.5 + Phantom lightweight (thanks ADCO).

    ETA: By "won't run", I mean it persistantly short strokes. Not every round but several per magazine. It runs like a sewing machine with the origional BCG.
    what kind of buffer you running?

  3. #13
    Join Date
    Jan 2008
    Location
    Cincinnati, OH
    Posts
    36
    Feedback Score
    0
    Quote Originally Posted by bkb0000 View Post
    what kind of buffer you running?
    I've tried both H and Carbine.

  4. #14
    Join Date
    Mar 2009
    Location
    Alabama
    Posts
    2,770
    Feedback Score
    0
    Quote Originally Posted by Tweightwee View Post
    I've tried both H and Carbine.
    Have you tried 5.56 pressure ammo?
    Also Have you tried replacing the gas tube?

  5. #15
    Join Date
    Jan 2008
    Location
    Cincinnati, OH
    Posts
    36
    Feedback Score
    0
    Quote Originally Posted by Thomas M-4 View Post
    Have you tried 5.56 pressure ammo?
    Also Have you tried replacing the gas tube?
    No to the gas tube.
    Yes to the 5.56. Privi 193, FC "green tip" and Winchester Q3131A.
    The Q3131A caused blown primers in this gun and a POF but not a different Bushmaster. I checked head space with a Field II gauge and neither gun closed on the gauge.

  6. #16
    Join Date
    Mar 2009
    Location
    Alabama
    Posts
    2,770
    Feedback Score
    0
    Quote Originally Posted by Tweightwee View Post
    No to the gas tube.
    Yes to the 5.56. Privi 193, FC "green tip" and Winchester Q3131A.
    The Q3131A caused blown primers in this gun and a POF but not a different Bushmaster. I checked head space with a Field II gauge and neither gun closed on the gauge.
    Chamber needs to reamed to 5.56 spec. probably you have extraction issues.
    POF? SORRY its hard for me to keep up with acrinims

  7. #17
    Join Date
    Jan 2008
    Location
    Cincinnati, OH
    Posts
    36
    Feedback Score
    0
    Quote Originally Posted by Thomas M-4 View Post
    Chamber needs to reamed to 5.56 spec. probably you have extraction issues.
    POF? SORRY its hard for me to keep up with acrinims
    POF= Patriot Ordinance Factory, a piston gun.

    All the empties leave the gun reliably. I have carbine extractor springs, inserts and O rings under all my extractors. I do get some brass shavings though.

  8. #18
    Join Date
    Mar 2009
    Location
    Alabama
    Posts
    2,770
    Feedback Score
    0
    Quote Originally Posted by Tweightwee View Post
    POF= Patriot Ordinance Factory, a piston gun.

    All the empties leave the gun reliably. I have carbine extractor springs, inserts and O rings under all my extractors. I do get some brass shavings though.
    Does it run Q3131 fine with the neutered BC ?

    My LMT loves Q3131 and xm193 if I could afford it that would be the only thing I would run.

    Popped primers are a classic sign of an out of spec chamber that needs to be reamed to a 5.56 standard.

    What kind of malfunctions are you getting Bolt over Base , Double Feeds.

  9. #19
    Join Date
    Jun 2006
    Location
    NoVA
    Posts
    10,780
    Feedback Score
    17 (100%)
    I've not yet met the AR that I can't get a M16 BCG group to work in, other than a sear blocked Colt lower......just sayin'.
    Chief Armorer for Elite Shooting Sports in Manassas VA
    Chief Armorer for Corp Arms (FFL 07-08/SOT 02)

  10. #20
    Join Date
    Jan 2008
    Location
    Cincinnati, OH
    Posts
    36
    Feedback Score
    0
    Quote Originally Posted by Thomas M-4 View Post
    Does it run Q3131 fine with the neutered BC ?

    My LMT loves Q3131 and xm193 if I could afford it that would be the only thing I would run.

    Popped primers are a classic sign of an out of spec chamber that needs to be reamed to a 5.56 standard.

    What kind of malfunctions are you getting Bolt over Base , Double Feeds.
    The popped primers happened with both BCs and both bolts in both BCs. But only with the Q3131A, and not with Privi or the, I misspoke earlier, LAKE CITY "green tip". I suspect the IMI loaded Winchester is a little hotter than other 5.56 ammo and is unforgiving on "tight" chambers.

    The only malfunction I get when using the new BC and NOT using the Q3131A is short stroking. The gun does not pick up the next round, closes on an empty chamber and does not lock open on the last round.

    I do want to find a Ned Christiansen reamer to resolve chamber problems beyond doubt.

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
  •