Case of the creepy pin

[Dustbuster]

Was at the range today. Last time I worked my 516 all was smooth as glass. Was shooting umc 55 grain life was good. Grabbed a new box of 62 grain 556 green tip by accident. After 200 rounds the rifle started doing a double tap after every 5 or 6 rounds. What a ahitty feeling.After the 3 rd time of this happening, I did an lti, cleaned the bolt piston, gas plug,went through everything, looked at the primers good to go. Reloaded 3 rounds fine then a double tap. Put it away and left for the house. Not wanting to fix something till its broke, I broke it out again pissed thinking your going back to sig bastard... On the left side the most forward pin holding the hammer walked itself out if the hole to where the hammer had enough slop to be labeled as the cause. I put the pin back in place all good cept the trigger feels like crap all gritty and nasty. Anyhow I guess I'll call sig on Monday to check on this and consider another hiperfire and pins I can safety wire. I knew about triple tap drama at other locations and thought this may have been heading that way...luckily it didn't Moral of this post if your ar starts doing a double tap on its own check your triggers hammer pins along with the other usual suspects.. Sent from my iPhone using Tapatalk 2 of course it ate my spelling.

Edited October 13, 2013 by Dustbuster

[TripleDigitRide]

Have you thought about trying the KNS anti-rotation pins? Edited October 13, 2013 by TripleDigitRide

[Oh Shoot]

I always hear/read that if hammer and trigger springs are within spec and installed correctly, the pins will never walk. Indeed that's what the indentations on the pins are for, the legs of the hammer spring to seat in them.

 

Look down in there and see if legs of hammer spring are sitting correctly next to wall of upper and not over the trigger spring loops or broken or something (I assume the Sig has conventional firing group parts construction?)

 

 

 

 

 

- OS

Edited October 13, 2013 by Oh Shoot

[smopoim86]

That picture looks like your bolt catch pin has backed out a little too. 

[Dustbuster]

Bolt catch is ok, hammer spring legs are correct and seated where they should be.. I may use the kns pins, used em on sig 556 w good results. Either way ill fix it. Shot fine today after I inspected and cleaned everything and put it back together.Heck I may pop a hiperfire in and kns pins... Well see but thanks for the suggestions!'n Sent from my iPhone using Tapatalk 2 of course it ate my spelling. Edited October 14, 2013 by Dustbuster

[Dustbuster]

Update found the kns kit on amazon for 30 bucks, cheap insurance I did order. Sent from my iPhone using Tapatalk 2 of course it ate my spelling. Edited October 14, 2013 by Dustbuster

[RWF]

love KNS, I always put them on. needed or not I like the way they look on the AR.