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12/8/2005 3:25:02 PM EDT
Fresh build with a Laeur/LMT Lower LMT Upper M-4 Stock with H Buffer. The pin will pop out and get stuck in front of the hammer preventing firing. I've put it in a number of times and for the life of me can't figure it out. Any ideas?hanks,Mike
12/8/2005 4:01:53 PM EDT
[#1]
I'm a big idiot folks. Looks like I spent to much time away from the black rifle. The buffer  tube is supposed to cover the pin.
12/8/2005 4:54:44 PM EDT
[#2]

Quoted:
I'm a big idiot folks. Looks like I spent to much time away from the black rifle. The buffer  tube is supposed to cover the pin.

Yep
12/8/2005 5:21:24 PM EDT
[#3]
Bet you won't forget that again.
12/8/2005 5:46:35 PM EDT
[#4]

Quoted:
Bet you won't forget that again.



heheheheheh
12/9/2005 12:51:47 AM EDT
[#5]
does your lower receiver extension have the timing lip on it?



Good one on the left, note the difference in threads


Different view of the lip
12/9/2005 1:48:18 AM EDT
[#6]
the lip of the buffer tube as pictured in tweak's post is whats suppose to be holding the pin in place
12/9/2005 3:46:38 AM EDT
[#7]
and the buffer goes BEHIND the pin.....not on top of it!
12/9/2005 7:55:24 AM EDT
[#8]
I dont think it had a lip. hmmm.

Incedently the pen bent the lower reciever where the pin is supposed to rest as the bolt slammed forward. Which explains now why the bolt wouldnt seat. The pin seems to be in place now but I'm concerned with the reciever bent the way it is it might come out or the reciever area would break off. It bent so much the paint came off of it. But I'd hate to throw the reciever away. Has anyone had any experiance with this?

Is there a certain kind of black paint to touch up the finish on an A/R
12/9/2005 9:11:39 AM EDT
[#9]
Why not post a picture so we can see what you mean...
12/9/2005 10:33:34 AM EDT
[#10]
bent or indented?
12/9/2005 10:51:08 AM EDT
[#11]
the lip and the indexed threads are what separate a good LRE from a POS.
12/9/2005 3:48:58 PM EDT
[#12]
I was at work... heres the image. Its kind of hard to make out the bend though but you can see the silver area is showing because the metal bent.
http://hometown.aol.com\pita229\arbent.jpg

and another

http://hometown.aol.com\pita229\arbent2.jpg

my tube

http://hometown.aol.com\pita229\tube.jpg
12/9/2005 4:20:33 PM EDT
[#13]
buffer detent is breaking through the inside of the lower?
12/9/2005 6:27:25 PM EDT
[#14]
Yes
12/9/2005 6:43:07 PM EDT
[#15]
Damn. The bolt carrier is supposed to hold the buffer off of the pin when the rifle is assembled. Looks like that is not happening. You lower will eventually fail is my guess.

Bob
12/9/2005 7:55:43 PM EDT
[#16]
Well the damage occured while the buffer tube was not screwed in enough to cover/lip the retainer pin. I dont know how much pressure the upper lip will recieve in the future to necessitate a new lower or if it will last forever.
12/10/2005 12:03:40 AM EDT
[#17]
I'm not seeing any impact marks on the face of the buffer as would be seen if the buffer was impacting the detent. Looks more like the detent came out of the hole and got mangled by the buffer.
12/10/2005 5:00:34 AM EDT
[#18]
Yes the buffer is fine. Its the lower reciever that is damaged and in question.
12/10/2005 6:07:57 AM EDT
[#19]

Quoted:
Yes the buffer is fine. It’s the lower receiver that is damaged and in question.



Since I don't see anyone replacing the receiver for free since the damage was on your part, here is a solution that could be a fix.
Note: The wall thickness seems to be on the thin side, Give the manufacture a call on the problem and you may be able to get a free replacement receiver.  If so, then the listed solution below is kind of mute, I will list it just incase you have to try to work with what you got.

Mark the receiver extension at the buffer retaining center pin.  Pull the receiver extension, and use a small round jewelers file to slot the bottom of the extension (read just the size of the middle post of the retaining pin.  Now while fully holding down the buffer retaining pin, screw the extension in over the top of it, and let the middle post snap up into the new grove a wind or two forward on the extension. Granted that this will retain the pin when the action is locked closed, it’s when you open the action up that you may want to do slowly (read a few good blows by the buffer unchecked by the carrier is going to finish off the crack and the retainer is going to go flying.

Note: don't go buck wild, you only want to screw the extension in about a wind or two more. Any more than this and you will have problems with B-B/C not going far enough back during the charging stoke and the bolt not making it past the bolt catch for bolt hold open on the last round.
12/10/2005 6:15:03 AM EDT
[#20]

Quoted:
I dont think it had a lip. hmmm.

Incedently the pen bent the lower reciever where the pin is supposed to rest as the bolt slammed forward. Which explains now why the bolt wouldnt seat. The pin seems to be in place now but I'm concerned with the reciever bent the way it is it might come out or the reciever area would break off. It bent so much the paint came off of it. But I'd hate to throw the reciever away. Has anyone had any experiance with this?




Buffer retainer pin only holds the buffer from coming out of the rifle with the action open.  When you close the action (upper/lower receiver), the back of the carrier pushed the buffer off the pin ans slighty back into the receiver extension.  

Also, if the pin is installed with the outer top edge under the receiver extension, and only the center of the protuding center pin above the extension face (just kissing the extension tube face), then the pin should never make contact on the bottom of the carrier, hence the reason for the bottom slot on the carrier.
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