My gun eats triggers

[barrysuperhawk]

Okay so I broke my gun again tonight, twice.

 

My gun is an ATI milsport although the only parts that are left from the original gun are the upper and lower receiver and the barrel. Everything else has been changed. The problem I have is this gun absolutely eats triggers I'm averaging less than 500 rounds before I break either a trigger or Hammer pin. I've gone through over a dozen combined, including some of the brand name non rotational varieties. I've actually limped through stages with painters tape on either side of my receiver to hold the broken pins in place so I could finish the match.  I've also replaced three Hammer Springs because I keep breaking the feet off of them.

 

I always assumed that it was because the ATI came with a stock mil-spec trigger, and I was replacing the parts that I broke with  mil-spec parts . Then I switched to and hiperfire EDT because I picked it up off a price table and after about four hundred rounds tonight it started doubling and tripling.  Obviously this is no bueno so I pulled that out and stuck in and Elfman drop in because that's what I happened to have with me at the time. The second stage with the Elfman was ridiculous I was getting failure to fire light strikes about every third or fourth round. At least with the mil-spec crap it was reliable Until It Broke, and no that's not a logical impossibility.  

 

When I pulled the hyperfire out I noticed that the engagement surfaces seemed a bit chewed up, but not too terribly bad, just enough that I would have expected about a 10 lb trigger pull.  

Now I'm pretty sure that the Elfman will work in the standard AR just fine, and actually the hyperfire with just a minimal amount of cleanup and maybe dressing the engagement services will probably also go into a five five six and be just happy. But that leaves me without anything to put into my gun except GI parts.

 

In case anybody is interested ATI is basically a new frontier lower and I am running a JP bolt JP carbine 308 spring and the kynshot hydraulic buffer.  

 

Having read through some of the other PCC trigger threads I gather that hyperfire and gissele are fairly popular with CMC coming in a close third.  Given how many broken pins I have suffered, I think that a drop in unit might be a better option than a traditional 2 pin setup. 

Obviously most everyone has a favorite, but I am interested in 2 things.  First and foremost I am interested in reliability.  It MUST go bang every time.  A close second is durability, how many rounds will it survive?  A distant third is the actual trigger pull.  I have comfortable at 4lbs or so, but I am also used to a FAL trigger, so I am not terribly hung up on pull numbers.  I also actively dislike straight and straight ish triggers, a standard curved trigger is better.  

 

So, what should I get? 

[kattman]

We are doing the KE Arms SLT-1 triggers in the blowbacks and the SIG MPX's with KNS anti-walk pins.   Good luck in Steel and USPSA so far, but hammer face takes a beating.  Also we are mostly doing your buffer/spring set-up as well as the TACCOM unit.  I am currently experimenting with the CMC 9mm and the ELFTMANN 9/45 for the MPX's and blowback PCC's.  Have the CMC in a 45 blowback (and a 22LR upper/SBR).  Both these as well as the SLT point out they are PCC capable.  Initial tests are GTG with great trigger pull and reset.  So far no hammer follow or doubling, but at low round count until our season starts back up her in Michigan.  All these are available in straight or curved.  No doubt that PCC's are extremely hard on fire control components.  Good luck--hope this helps in your investigating.  FYI, I have bunches of failed PCC "experiment" triggers/parts in the "used" bin.

 

Note--JMHO

 

Kattman from Michigan

[Bwillis]

@barrysuperhawk what bolt are you using? To me it sounds like your bolt is non ramped and is beating the hammer back vs being ramped and setting the hammer back. 

[MemphisMechanic]

44 minutes ago, Bwillis said:

@barrysuperhawk what bolt are you using? To me it sounds like your bolt is non ramped and is beating the hammer back vs being ramped and setting the hammer back. 

This.

 

But also I second the KE Arms SLT. Pretty good feeling trigger, but most importantly it has no conventional sear to get smashed by the hammer coming back. You’ll see a huge reduction of stress on the disconnector, and without the stress from the hammer coming back into it? You should stop breaking pins.

 

I’ve run one. It does what they claim. There’s an interesting and unique feel to it, but it’s not long and it’s not heavy.

 

 

Edited January 31, 2020 by MemphisMechanic

[Salsantini]

1 hour ago, Bwillis said:

@barrysuperhawk what bolt are you using? To me it sounds like your bolt is non ramped and is beating the hammer back vs being ramped and setting the hammer back. 

Agree. If it is not ramped the bolt would hit lower on the hammer and will cause additional stress on the pins and the holes in the receiver

[AHI]

From your description . The fact you have a JP bolt and other proper components.

Just A guess your pin holes are out of speck .probably a little high.  

. 

[barrysuperhawk]

I swapped out the stock bolt that came with the gun with a JP 9 mm bolt, I've never heard anybody say anything bad about the JP's so I assume that it is the proper geometry