Large pin or Small pin on AR trigger?

High Binder

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Hey guys, just a quick question. I have a 6.5 Grendel upper now in addition to the usual .223. Anyway, I need to upgrade the trigger in a bad way. However, I have no idea how to figure out is my current (OEM) trigger is small or large pin. What pin is this spec referring to?

The lower is Bushmaster circa 1990s.

Thanks in advance!
 

High Binder

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Re: Large pin or Small pin on AR trigger?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: 308sako</div><div class="ubbcode-body">The diameter of the small pin is .155" I do not think that anyone but Colt has used the larger .175" size.

A micrometer is your friend </div></div>

Sounds like I have a small pin but what pin does this dim refer to?

Thanks for the info!
 

ply1951guy

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Re: Large pin or Small pin on AR trigger?

The dimension is referring to the diameter of the pin that holds the trigger in the receiver.
 

Chiller

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    Re: Large pin or Small pin on AR trigger?

    <div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: 308sako</div><div class="ubbcode-body">The diameter of the small pin is .155" I do not think that anyone but Colt has used the larger .175" size.

    A micrometer is your friend </div></div>

    Winner winner.....chicken dinner.....
     

    kbrady

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    Re: Large pin or Small pin on AR trigger?

    Sorry to hop in your thread, but my Colt Match Target HBAR has the large pin in it, anybody have a clue when they switched from the small pin to the large one?

    Kelly
     

    kbrady

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    Re: Large pin or Small pin on AR trigger?

    I might have read somewhere they started using the large pin in the late 90's, early 2000's. I could be wrong, don't hold me to that.

    Kelly
     

    KTDLS7

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    Re: Large pin or Small pin on AR trigger?

    Remember, this is Al's Internet . . .

    Contemporary Colt "LE/Mil" models are small pin (i.e. LE6920, LE6940, etc.)

    The old Colt "green box" ARs were small pin. If my memory serves me, in the early 90's Colt changed the lower to prevent FA sear/trigger group installation and went "large pin". These were "blue box civilian" models. For clarification, green box / blue box referred to the color of the box end panel label.

    Kevin