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KingCobra
09-15-11, 18:10
the pin in my lower reciever that holds the hammer on keeps slightly backing out. its staying in both halves of the frame but..

1. i dont want to keep adjusting it.
2. it worries me it may come out enough and snap it when the hammer flies foward from the spring tension


the pin is snug, and takes a hard push to get it in flush with my reciever but so much as one rack of the bolt and it back out on the left side of my frame. can i just use some thread lock or a tab of superglue?
Quiet-Matt
09-15-11, 19:26
I borrowed this picture from another site. Make sure that your hammer has the retaining spring or "J" spring. This is what keeps the hammer pin form walking. The spring engages a groove in the center of the pin. Check for the J spring and report back.

You can see it inside the hole...
http://i300.photobucket.com/albums/nn33/Noah_Zark/Noah_Zark01/DSC09400.jpg

-Matt
jet80tv
09-15-11, 19:35
And they say KNS pins are not functional or necessary!;)
KingCobra
09-15-11, 19:39
And they say KNS pins are not functional or necessary!;)

kns pins??

those the ones were there hoth connected?

anyways, do i need to pull my hammer out to view that? honeslt, I'm new to owning my own m4, so I have never taken my lower apart..


*EDIT* screw it, i pulled it apart anyways, looks my hammer has that pin,BUT its not very big, its very little...
Quiet-Matt
09-15-11, 20:05
If the spring isn't large enough to engage the groove in the pin properly, it may be where your problems are coming from. While you have the hammer out, re-insert the pin and see if it provides enough tension to stay in. If not I'd look for another hammer.

-Matt
Eric
09-15-11, 20:16
On a rare occasion, you might end up with a hammer pin that has an unusually shallow groove cut into it, which does not give the spring much engagement.
KingCobra
09-15-11, 21:21
If the spring isn't large enough to engage the groove in the pin properly, it may be where your problems are coming from. While you have the hammer out, re-insert the pin and see if it provides enough tension to stay in. If not I'd look for another hammer.


-Matt

On a rare occasion, you might end up with a hammer pin that has an unusually shallow groove cut into it, which does not give the spring much engagement.




its pretty dang tight. its not wobbling at all, i just had to use a hammer to get the pin back out of the hammer.


the problem seems to only happen when the hammer is in the rifle..I'll take a picture to show how much the pin is moving out..maybe i'm just paranoid?
Col_Crocs
09-15-11, 22:11
A couple of questions...
1. Is the pin groove properly centered?
2. Does this happen to your trigger pin as well?
My take on it is, it shifts to stick out on one side as a result of the J-spring settling into the groove. Why it does that could either be a pin or lower issue. If it's minimal, I would let it be.
jet80tv
09-16-11, 10:30
Do both your hammer and trigger pins have two sets of grooves so that they may be interchanged? If so try switching them.
Iraqgunz
09-16-11, 12:16
That's correct because they aren't. You simply replace the worn hammer or pin or whatever the cause is, rather than using a band-aid.

Properly assembled and quality lower parts rarely fail.


And they say KNS pins are not functional or necessary!;)
Tango-Alpha
09-17-11, 09:27
kns pins??

those the ones were there hoth connected?

anyways, do i need to pull my hammer out to view that? honeslt, I'm new to owning my own m4, so I have never taken my lower apart..


*EDIT* screw it, i pulled it apart anyways, looks my hammer has that pin,BUT its not very big, its very little...

:dance3: Congrats! Taking apart or assembling your own LPK is the best way to learn about how your AR functions. Not being familiar with AR's, it gave me a clear understanding of the mechanics involved when I assembled my first lower with an LPK. Should you decide to purchase another AR, I'd recommend assembling one from stripped components. It's very rewarding.
KingCobra
01-24-12, 17:40
I just want to say sorry I never came back to this thread, computer issues, life issues etc, and i forgot bout this site until i broke out my m4 again.

anyways, somewhere along the way i got it to stop backing out. i never found the issue but it doesnt do it anymore.

it just freaks me out being a dpms lower...
11am1a
01-24-12, 22:37
its a DPMS lower, what did you expect...
KingCobra
01-25-12, 16:57
I built my whole m4 for 200$. so i didn't expect alot.