KNS pins and CMC trigger for an AR

[MMcfpd]

Forgetting for the moment the question of whether or not anybody actually needs them, I've got a question regarding KNS Precision pins and a trigger I've been looking at. Specifically, I've been considering a Chip McCormick trigger, and the self-contained nature of that unit makes me wonder if it doesn't render the KNS pins superfluous.

 

[DBR]

The Chip McCormick trigger comes with pins that use E-Clips. The stock pins don't work there is nothing to hold them in the receiver. The KNS pins work much better.

I only use the McCormick trigger on a recreational gun not one which might ever be used for self defense.

 

[MMcfpd]

I didn't know that the CMC trigger required new pins. Do you use the KNS pins with the McCormick trigger then?

I only use the McCormick trigger on a recreational gun not one which might ever be used for self defense.

Why is that?

 

[Onmilo]

Chip McCormick trigger pack uses seperate, longer, non-mil-spec trigger pins that are retained with 'e'-clips to hold the trigger pack in the receiver.

KNS trigger/hammer pins are precision machined stainless steel forgings that work only with standard semi auto or full auto mil-spec trigger/ hammer assemblies.
They fit tight and do not rotate in the receiver holes like standard Mil-Spec pins do.
KNS trigger.hammer pin set Will Not work with a Chip McCormick trigger pack.

 

[MMcfpd]

That's information I needed. Thanks, Onmilo.

 

[DBR]

KNS pins do work with the CMC trigger! I have them on one of my lowers and my buddy has them on his. The KNS pins are not forgings. They are machined from 416 SS bar stock (this info is direct from KNS). They are precise. You have to use the standard diameter pins to fit thru the CMC trigger housing bushings - NOT the oversize pins.

I would not use the CMC trigger on a serious rifle for three reasons:
1) A 3 1/2# trigger is too light for my serious use rifles. I cannot feel it with gloves on without possibly firing it.
2) There is no takeup on the single stage version. It is very crisp but does not move before it breaks therefore there is no warning of let off. The two stage has take up but IMO is still too light.
3) The hammer/sear engagement is much less than a stock trigger and could be subject to "bump off" if the rifle hit something hard like a door frame or was dropped.

Some of these characteristics may be considered benefits on a range gun. I like the triggers for their stated use: "Match Trigger".

The E-Clips provided with the trigger can and do catch on clothing etc and pull off the pins. The pins are also longer than necessary and protrude from the sides of the receiver.

 

[Coronach]

Hmmm.

Anyone know if the KNS pins work with the RRA NM trigger, as tweaked by ADCO?

Thanks,
Mike

 

[Bartholomew Roberts]

The RRA uses (or used to when I bought one several years ago) slightly oversize standard pins, so the KNS should work; but you might need the pins that are about 0.001" oversize.

The main advantage of the KNS pins on a semi seems to be that they give a better trigger feel, even with a stock trigger. They also prevent the firing control pins from egging out the lower receiver; but considering that a local guy ran 160,000 rounds of nothing but full-auto before he encountered any issues with standard pins, I don't know that they add much for semi use.

 

[MMcfpd]

I'm glad I asked. I now see that Talon actually markets the KNS pins and the CMC trigger together.

 

[Onmilo]

Oh man I have to apologize.

The KNS pins I am referring to are not the anti rotate pins that use external locking tabs.
I actually forgot that these guys produced something like this.

The KNS pins I am referring to are over Mil-Spec dimension solid MATCH Pins that are slightly larger than the nominal service dimension of .154" diameter.
They are made for use in Service Match rifles that cannot display any outside modifications that would alter the weapon from Service standards.
These specific pins cannot be made to work with a Chip McCormick trigger pack.
The McCormick trigger pack must use pins that are even smaller than .154" in diameter and they must be retained on the outside of the receiver because the through holes in the McCormick trigger pack are smaller in diameter than the through holes in the AR15./M16 receiver.

As a footnote the McCormick trigger cannot be used in a rifle intended for Service rifle competition.
It can be used in a rifle made for Open class or Free rifle classifications.

The rifle I have my McCormick trigger pack installed in is used for 300 meter free shooting.

If I confused you with my post I apologize.
I should have clicked your link first to see exactly what type of pins you were referring to.