I just installed a Geissele trigger in my Bushy lower and noticed that after cycling the the trigger about 20 or so times that the hammer pin and the trigger pins seem to be slightly protruding more on the right side of the receiver.  I tapped them in and they fit snug but now they seem to be moving.  Maybe I didn't have them in properly to begin with.  I installed them from the left side of the receiver with the grooves on the left side.  Should I be considering the KNS anti-walk pins?  Can you use the KNS pins with a Geissele trigger?  

Any advice would be greatly appreciated.

Thanks!
ErnieB

dont know about the trigger but it should have one of the legs on the hammer spring holding the trigger pin by the groove.

there is slight left to right movement but not falling out and i use the kns pins on my cmc triggers with no ill effects.

Quoted: I just installed a Geissele trigger in my Bushy lower and noticed that after cycling the the trigger about 20 or so times that the hammer pin and the trigger pins seem to be slightly protruding more on the right side of the receiver.  I tapped them in and they fit snug but now they seem to be moving.  Maybe I didn't have them in properly to begin with.  I installed them from the left side of the receiver with the grooves on the left side.  Should I be considering the KNS anti-walk pins?  Can you use the KNS pins with a Geissele trigger?   Any advice would be greatly appreciated. Thanks! ErnieB

I received this e-mail from Geissele's:

Gentlemen,

Do to the large variation of AR15 receiver holes there have been cases where the hammer pin wants to walk out with our trigger.  To prevent this Bill has an oversize pin available (0.1562" dia vs. 0.1557" dia).  The pin comes with a corresponding larger hammer trunnion with a heavier retaining circlip.

If you are having issues with retention of the hammer pin please send the hammer back to Bill and he will retrofit the new parts at no charge.  He would like to just send the parts out but due to the tight tolerances the parts need to be individually fit to each hammer.

Send the hammer to:
William Geissele
603 Caroline Dr.
Norristown, PA 19401

If you do not have a problem with your hammer pin it is not necessary to perform this retrofit.

Bill can be reached direct at [email protected] if you have any questions.

Have a great night!
~Amy

I use KNS pins on my AR10 and have experienced no problems

Ernie,

Did your trigger come with a separate small envelop with a 3-Groove Oversized Hammer pin?  Either way please contact me directly via our website and we will fix you up.

Bill
www.geissele.com

Quoted: Quoted: I just installed a Geissele trigger in my Bushy lower and noticed that after cycling the the trigger about 20 or so times that the hammer pin and the trigger pins seem to be slightly protruding more on the right side of the receiver.  I tapped them in and they fit snug but now they seem to be moving.  Maybe I didn't have them in properly to begin with.  I installed them from the left side of the receiver with the grooves on the left side.  Should I be considering the KNS anti-walk pins?  Can you use the KNS pins with a Geissele trigger?   Any advice would be greatly appreciated. Thanks! ErnieB Sounds like they are protrudingly evenly? Sometimes they look like they are sticking out too far on some receivers.  Go shoot it and I bet they stay where they are.

Yeah, my pins stick out a little, but they dont move.

My pins are flush on the left side of the receiver and stick out slightly on the right side.  I am going to put about 500 rounds through my gun this Wednesday so I will use that as a test to see if they stay put.  It just looked a bit odd for them to be protruding more on one side.  

Bill, is it okay to use KNS pins with your trigger?  My kit did come with the oversize hammer pin.  The smaller pins did need a bit of a tap to seat them in my lower.  Should I try the larger pin? I appreciate the offer to remedy the situation but first I am going to make sure that I really have a problem before sending the hammer to you.  I really, really like the trigger and recommend it to anyone.  I have been shooting a stock trigger and find this to be a big improvement.  Perhaps that is why I am not used to seeing the pins protrude out one side of the receiver.  I manually cycled the the trigger about a 100 times and the pins initially moved to the point they are at now and don't seem to be moving any further.  Is that normal?  Forgive my ignorance.  I carry my AR to work with me everyday so I want to make sure the fire control system is sound.

Thanks for the info guys.

Ernie,

If there is a good 'tap fit' to the pins you are ok.  I have never seen a trigger pin walk out.  Before I started including the 3 Groove pin last year about 1 in 20 triggers had a hammer pin walk. Now with the extra oversize pin (0.1562"), the heavier circlip and updated trunnion this has pretty much taken care of any problems.

I don't recommend the KNS pins because the hammer pin retaining mechanism on my trigger is different than stock.  Stock has a "J spring" that locates on a center groove on the pin.  My pin does not have a center groove but has a small groove next to the main side groove.

A circlip will snap into this small groove and keep the pin in the hammer.  However, the circlip will allow the pin to float about 0.020" back and forth.  This allows the hammer and pin to find a point of equilibrium so the hammer has ZERO drag on the pin.  

The stock J spring will drag on the stock hammer pin.  This is why the pin will turn in the receiver holes on a stock trigger.

Since the KNS pins do not have the side groove the circlip on my trigger will drag on the KNS pin.  It will work but soon the circlip will be enlarged from the constant rubbing.  This would only be detrimental if the Geissele pin was then reused in place of the KNS pin.....the circlip would be too weak to hold the Geissele pin.

I would shoot the weapon and if there is any indication that the pin is moving just tap in the 3 Groove pin.

Send me an email and let me know how you make out.  If there are any problems we will take care of them.

Good Shooting,
Bill

Thanks Bill.

I appreciate the reply.  I just picked up 2 cases of Lake City SS109 and will give the trigger a thorough work out this week.  I'll take your advice and tap in the larger 3 groove pin if the hammer pin starts to walk.

Take care,
Ernie

I went and finally shot my new trigger.  I REALLY REALLY REALLY like it!  The hammer pin walked a small bit but did not move any further.  It seems to be staying put.  It just looks a bit odd.  I only ended up shooting about 200 rounds before some friends arrived and I ended up shooting my Glock for the rest of the day.  I will shoot some more later this weekend.  

I do have a question regarding the sear adjustment.  According to Bills directions you should adjust the sear engagement off until the trigger essentially becomes a single stage trigger.  Readjust the engagement until the second stage returns then add an additional quarter turn.  This is how I have my trigger adjusted and it is a great two stage trigger however, I have read in some posts that it sounds as if some are adjusting the sear engagement so light that the trigger feels like a single stage when you stroke through it.  Is this advisable?  Does it matter if the sear engagement is adjusted that light?  Did I misunderstand the adjustment?

Just curious.

Thanks,
Ernie