Hammer/Trigger pin hole wear

[SHERWINVILLARETE]

Just curious, is it normal for the black anodized layer to start chipping off after thousands of rounds? My lower is showing some aluminum inside the hole now.

[matemike]

I have never noticed that on my BCM, DD or S&W lowers.
Start by telling us what kind yours is.

Are you removing the fcg pins to see it? My initial thought is if the pins aren’t falling out (which they shouldn’t per their design) then don’t worry about it.

My buddy had a take down pin on a benelli shotgun that would slip out either direction just with gravity. So truth is that any pin hole could potentially wear out, however that is a completely different design pin system than an AR-15 fcg. He put duct tape over both sides and continued hunting with it though.

[SHERWINVILLARETE]

I have never noticed that on my BCM, DD or S&W lowers.
Start by telling us what kind yours is.

Are you removing the fcg pins to see it? My initial thought is if the pins aren’t falling out (which they shouldn’t per their design) then don’t worry about it.

My buddy had a take down pin on a benelli shotgun that would slip out either direction just with gravity. So truth is that any pin hole could potentially wear out, however that is a completely different design pin system than an AR-15 fcg. He put duct tape over both sides Andy continued hunting with it though.

Aero lower. It's sorta like a faded blackish aluminum. Not literally chipping but more like fading. Still measures the same diameter.

Going to run the KNS anti walk out pins for insurance.

[GH41]

Aero lower. It's sorta like a faded blackish aluminum. Not literally chipping but more like fading. Still measures the same diameter.

Going to run the KNS anti walk out pins for insurance.

What will the KNS pins do other than make your wallet lighter?

[docsherm]

What will the KNS pins do other than make your wallet lighter?

They hold the pins in place for triggers that are actually used, as the lower wears out and the holes get bigger. I have an SBRed DPMS lower that is almost 20 years old and has over 55k through it. It is on its 4th trigger. It has KNS pins because when you actually use something it will wear out, no matter if it is an Anderson Arms lower or a Colt.

OP- what trigger are you using? The pins and the lower may be slightly off. That can cause some movement and additional wear on the parts.

[RobertTheTexan]

Aero lower. It's sorta like a faded blackish aluminum. Not literally chipping but more like fading. Still measures the same diameter.

Going to run the KNS anti walk out pins for insurance.

Another option are CMC trigger pins. I’ve used KNS and they are GTG, but lately have been using CMC trigger pins. The CMC pins are a similar concept without the little bar. They are essentially two of the rear KNS pins, if that makes sense. Two threaded pins and I dab a little blue Loctite on - a very little, tighten down but not overly tight and you’re done. I like the CMC version only because they look a little cleaner.

[SHERWINVILLARETE]

I'm running a milspec trigger. The KNS pins not only prevents wear and walk outs but also improves trigger creep and reset. I love it

[SHERWINVILLARETE]

Another option are CMC trigger pins. I’ve used KNS and they are GTG, but lately have been using CMC trigger pins. The CMC pins are a similar concept without the little bar. They are essentially two of the rear KNS pins, if that makes sense. Two threaded pins and I dab a little blue Loctite on - a very little, tighten down but not overly tight and you’re done. I like the CMC version only because they look a little cleaner.

I did look at those. One thing that I didn't like about the CMC is that the hammer pin doesn't have the groove in the middle for milspec triggers. It's more ideal for drop ins. but im sure it works fine on a milspec. Just me being extra, I didn't want the hammer sliding inside the lower.

[lysander]

1) don't remove the pins unless absolutely necessary. Pulling them in an out is probably more detrimental than the slight rotational movement they normally see.

2) hard anodizing can be polished by rubbing, that is what you are likely seeing.

3) yes any time metal rubs on metal, you will have wear, put a little grease on the pins and don't mess with them until 5 or 6 k rounds

[markm]

I swear I'm on Arfcom.

pin holes don't wear out unless there's some underlying and wildly unusual circumstance. If the KNS concept was worth a shit, Geiselle would have employed the notion in his triggers.

Look at some of KNS's other goofball offerings, and you can get an idea of the nonsense they're all about.