Walking trigger and hammers pins

I see guns with anti walking pins all the time and see them for sale everywhere, Is this a common occurrence? I have never had one walk out that I can remember. Now I might imagine some of those old M-16’s that has had numerous rounds through might do it. A couple of my older AR’s and My M-16 carbine has some rattle between the upper and lower from a ton of firing.

Thought maybe it’s a new thing but I have newer rifles that hasn’t done it, is these pins a legit thing or just more decorations. I guess they wouldn’t be a bad idea on a rifle that will be used hard.


The only time I have seen trigger pins that started walking was on our issued M16s and M4s that had a fairly high round count. On top of that, it was always when the weapon was being fired on full auto or repetitive cycles on three round burst.

Now, with that said, I did go the KNS route on my last build and used anti-walk pins. Something I did notice was that the trigger pull on it feels just slightly heavier than on my other three builds that use the very same manufacturer trigger without anti-walk pins.

A lot of folks do this for piece of mind and I can understand it. If someone plans on a high round count under rapid fire (training classes or competition) then having some extra insurance on reliability doesn’t hurt.



My XDE is back in Ill. for the trigger pin walking out right now. Hope it gets resolved.


Only trigger pins that walked on me were on the PCC build. The Quarter Circle Ten lower kept having the Geissele pins walk out. I use KNS now for peace of mind


I can see this happening with full autos but I doubt us civies will get much out of it besides a piece of mind. Now , this might be an issue with budget guns due to some of them using cheap chinese parts but ive never experienced it. The rifle I used for training courses was a Colt 6920 and it has about 7500 rounds through it with no issues. Its been through at least 50 mag dumps in its life and been through alot of beatings. I personally wouldnt feel the need to use them unless I had a giggle switch, ymmv.


Walking pins is usually a sign of someone that can’t put the trigger group back together correctly.

I’ve owned 4 M-16 guns, one being a 9mm and never had an issue with them walking and they all had at least 30K rounds through them.

Pic of 9mm in question.



I’ve put together dozens of ARs and have services/ repaired hundreds. Usually I agree but as I stated above every once in awhile you get the lower with just slightly too large of holes (high round counts with rapid fire) or like my QC10 lower it just came that way from factory


Agreed. I’ve put quite a ew AR’s together, repaired others for friends, and was armorer trained in the military. Though rare it does happen, especially to high round count weapons.

Yes, an improperly assembled FCG can walk but in the military messing with the FCG was a huge no-go for joe grunt as you know. The older ones would but from what I saw first hand that was not the cause.

Bottom line, shit wears out sooner or later or an out of spec lower slips through the QC process.