Warning

 

Close

Confirm Action

Are you sure you wish to do this?

Confirm Cancel
BCM
Member Login

Posted: 12/17/2003 8:07:24 PM EDT
I am having a problem with my AR.  During rapid fire the hammer and trigger pins start to walk out a little.  I have never taken the trigger group apart, but I don't know if the previous owner did. Lower is a PWA pre-ban.  Anyway, I purchased a set of Bushmaster anti-walk pins to try to rectify the situation but they are too long!  Why is this, and is there any other way I can fix this?  It would seem to me that the longer pin would get inadvertantly pushed back and forth thus enlarging the holes.  Somebody please help me!!!
Link Posted: 12/17/2003 8:31:08 PM EDT
[img]http://www.bushmaster.com/shopping/lowers/Images/ANTIWALK.jpg[/img]

The anti-walk pins have two small washer sort of things that you clip on to the sides that will prevent them from moving. They are supposed to stick out the side a little, but with the washer sort of things on them, they wont move.
Link Posted: 12/17/2003 8:39:49 PM EDT
[Last Edit: 12/17/2003 8:41:02 PM EDT by JackBurton]
With the washers on I still get about 1/8" movement!  I really need a solution here or I am going to be trashing this reciever!  I am pissed!
Link Posted: 12/17/2003 8:56:57 PM EDT
Well, that sure doesnt sound normal, or at least compared to my exprience with them. I have a set of these in a lower that I had problems with and they dont have any movement?
Link Posted: 12/17/2003 9:07:46 PM EDT
I'm going to call Bushmaster in the morning.  Maybe they sent me the wrong pins.  I am really bummed about this.  If I can't get the right pins, what the hell am I going to do!!!
Link Posted: 12/17/2003 9:31:40 PM EDT
[url]http://ar15.com/forums/topic.html?b=7&f=22&t=184089&w=searchPop[/url]
Link Posted: 12/17/2003 10:59:27 PM EDT
Jesus Mirimba!!!!  Order sent!
Link Posted: 12/17/2003 11:21:53 PM EDT
The receiver has nothing to do with holding the pins in place. The hammer pin is held in place by the J spring in the hammer it locks into the detent cut of the pin and keeps it from walking. Then the legs of the hammer springs lock into the detent cuts of the trigger pin keeping it from shifting. I think you most likely have some springs installed wrong as they lock each other in place.
Link Posted: 12/18/2003 6:01:07 AM EDT
What David Hineline said... I've had the same issue in the past and it corrected nicely by making sure the hammer spring was in the pin groove.
Link Posted: 12/18/2003 6:10:20 AM EDT
Well if you have no other option but to use the anti-walk pins, and the ones you currently have are the correct length, if they are not too long you could try looking at Lowes or Ace Hardware for some thin washers to slide under the heads of the pins to take up the space. Add the washers under the heads of the pins like shims. I don't think a few .000's play will ruin your hammer or trigger pin holes.
Link Posted: 12/18/2003 6:49:44 AM EDT
And the correct answer is:

Originally Posted By David_Hineline:
The receiver has nothing to do with holding the pins in place. The hammer pin is held in place by the J spring in the hammer it locks into the detent cut of the pin and keeps it from walking. Then the legs of the hammer springs lock into the detent cuts of the trigger pin keeping it from shifting. I think you most likely have some springs installed wrong as they lock each other in place.
View Quote
Link Posted: 12/18/2003 7:34:25 PM EDT
I replaced the fire control group today and it seems to have worked, plus I found an M16 trigger in there which I destroyed and discarded.  It looks like the old hammer's J pin was bent of something because it was not locking the pin.  Stil feels a little loose, but I'll see when I get to the range.  Thanks!
Link Posted: 12/19/2003 5:08:24 PM EDT
JackBurton;

You can't solve this problem with C clips on the pins, or shims.  As long as the pin can travel, and/or rotate, there is the potential for movement on the lower.  There is a fix...call Steve at Guncity USA in Nashville.  Have a cup or three of coffee handy, and be ready to talk, actually, listen.  He's a small arms specialist that served in Vietnam, and has the most asskickin' guns I've ever seen, from 1911's (Colts) to his BM's.  The # is 1 615 256-6127.

Good Luck,
Mike
Link Posted: 12/23/2003 2:03:44 PM EDT
I am using the KNS pin setup sold by Denny's Gun or Global Tactical Supply.  They are really easy to install and work great.
Link Posted: 12/23/2003 3:17:21 PM EDT
Originally Posted By new-arguy:
Well, that sure doesnt sound normal, or at least compared to my exprience with them. I have a set of these in a lower that I had problems with and they dont have any movement?
View Quote


The hammer pin does have rotational movement when the hammer is released forward. Side to side movement is non-existant when you fire.

Mike
Link Posted: 12/23/2003 10:42:03 PM EDT
I use the KNS pins........., there awesome!!

RU4FREEDOM---out
Link Posted: 12/24/2003 1:56:16 AM EDT
WOW, that was deja-vu.  When I first bought my PWA Commando I took it to the range and the pins walked after about 20 rounds.  Not knowing anything about AR's, I bought the anti-walk pins too.  Then I read a take-down manual and realized that the previous owner installed the springs upside-down.  The gun functioned, but there was very little tension on the pin detents, so they walked.  I haven't had a problem since.

I learned a valuable lesson... just knowing how to make the gun go boom does not mean you "know" your weapon.
Link Posted: 1/2/2004 5:44:54 AM EDT
Top Top