AR-15 Trigger pin broke

Ive been trying to figure out why my new ST22 would only shoot once or twice then the hammer wouldnt reset. It has a 1.5# Jard Adj trigger. Another of my ARs has a 3# Jard Adjustable trigger and i could swap lowers and it shoots fine..


Last night i decided to swap the #3 and the 1.5# springs. Well as soon as i got the pin halfway out of the ST22 lower part of the pin fell out..
Found the problem pretty quick..

Cell phone pic... real camera is MIA..

You kant have nuttin nice!

Unusual...
It's typically the hammer pins that break and right in the same place so a visual inspection reveals nothing.

Prolly gonna get some good pins before long.. Dont want that happening in the middle of a hunt.

I have NEVER in all my range time ( and trust me it has been a hell of a lot) seen a broken trigger pin. Was it one of the fat cheap pins? or a chromed mil spec small dia (1.54") pin? I have seen them 'walk' out and cause an unexpected, but not catastrophic , failure but NEVER break. Although most of my experience has been with the M-16 and not the ARs. Is this a common failure?

The pin is whatever DPMS sells in their lower receiver parts kit. I have the same stuff in 2 other of my ARs and have alot of rounds thru them. This pin is in a AR that has a dedicated 22 upper on it. Only 500 or so 22rds and zero .223s. Ive never seen it happen thats why i posted it up. Im gonna invest in some antirotating pins some day.

Check for any marks or shine on "top" of the disconnector. I'll bet the hammer is smacking the disco which is held in place by the trigger pin. If you're using light hammer springs, this could be why it broke.

VegasSMG wrote:Check for any marks or shine on "top" of the disconnector. I'll bet the hammer is smacking the disco which is held in place by the trigger pin. If you're using light hammer springs, this could be why it broke.

Its a Jard Adjustable trigger, i have it setup like the instructions say and my other AR has the same trigger in it setup the same way..

BUT ill surely check that out when i get home. Thanks for the info.