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Invictus77
March 30, 2017, 18:53
A friend bought his brother a new Anderson AR for Christmas. From the first day, sometimes the trigger would not reset. My initial thought was it needs a little "break-in" time and then some lube. A few weeks and a couple hundred rounds later, there is no joy in Mudville.

In playing with the lower and looking it over I could not see what or why. I had a complete Colt HTS & springs sitting here that were replaced with a Geissele and started trying one new part at a time. Changing just one of the H, T, S or springs it was fine. Nothing I could find told me which was the "bad" part or "weak/stiff" spring :facepalm:

All is good now with all the trigger group replaced. The owner will be quite happy with the outcome. I am however not happy.

It is still sitting here in front of me and bugs the crap out of me I don't know what might be the real issue.

Ideas from the tribe???

tdb59
March 30, 2017, 18:59
A friend bought his brother a new Anderson AR for Christmas. From the first day, sometimes the trigger would not reset.

Ideas from the tribe???

Anderson FCG ?


If so, their crap is one step below Don't Purchase Malformed Shit.

Undersize disconnector ?

..............

TerryN
March 30, 2017, 19:11
Undersize disconnector ?

..............

My guess from 5,000+ miles away is a disconnector that needs fitted.

MAINER
March 30, 2017, 19:28
"A friend bought his brother a new Anderson AR for Christmas."

Poor geometry of engagement surfaces. I am a little less than enthusiastic of Anderson parts. I cannot fault them for the quality at their price point and I know they work "most of the time", but you've got to expect a lemon now and again.

Trigger groups are not a good place to economize. The ALG Defense QMS or the better ACT is a good place to start.

Disconnector is a good bet, this is usually a stamped piece and is found with burrs, ridges or just not ground correctly.

W.E.G.
March 30, 2017, 19:46
If taking it apart, and putting it back togther "fixed" it, the problem was most likely the hammer spring installed improperly (backwards or legs going wrong way).

Invictus77
March 30, 2017, 20:41
If taking it apart, and putting it back togther "fixed" it, the problem was most likely the hammer spring installed improperly (backwards or legs going wrong way).

Nope (although I have put the hammer spring in backwards myself in the past). Re-read the OP bro.

To other comments above:

Yes a complete, new Anderson rifle is what I understand it is. I have assembled some great rifles on Anderson lowers, but never have used an Anderson trigger group.

The disconnect was my first thought (yes I called it a sear in the OP :tongue: ) and was the first piece I changed and it fixed the problem. I ALSO put the Anderson disconnect back in with a new trigger that fixed it as well, which added to my confusion. All parts were changed one at a time with the original stuff and only ONE new part. All those combinations worked fine except all the original Anderson parts.

The reason I did what I did and posted it here was to try to understand the what & why. No argument it is probably the disconnect, but why?

I know this is hard for even experts to guess at without having in in hand, but if possible, what more should I probably look at closely? Angle, length, smoothness, other?

Thanks gents :cheers:

meltblown
March 30, 2017, 21:05
Lower parts kit is cheap..


Geissele is my only AR TG

Fn/form
March 30, 2017, 22:25
Anderson FCG ?


If so, their crap is one step below Don't Purchase Malformed Shit.

Undersize disconnector ?

..............

Said company of malformed origins has supplied Colt with parts for their mil rifles, per Colt armorer instruxtor. In-spec parts is in-spec parts.

That said, I've seen DPMS factory rifles with barrel nuts torqued so far past norm it shot crooked and barrel couldn't be removed without damaging upper receiver....

Fn/form
March 30, 2017, 22:27
...

The reason I did what I did and posted it here was to try to understand the what & why. No argument it is probably the disconnect, but why?

I know this is hard for even experts to guess at without having in in hand, but if possible, what more should I probably look at closely? Angle, length, smoothness, other?

Thanks gents :cheers:

Tolerance stacking in sum of OEM parts such that one "better" part puts in back in operation?

1769
March 31, 2017, 05:27
Lower parts kit is cheap..


Geissele is my only AR TG

Geissele have a great rep, but I have a Timney in my AR, and I'm very happy with it. Of course the price was right( Free ), so this may have been a contributing factor. :whistling:

sjohnson
March 31, 2017, 09:20
Tolerance stacking in sum of OEM parts such that one "better" part puts in back in operation?

^^^ This