Not resetting.

[Endall]

  I was shooting some mid power 10mm in my Elite Match last week and the trigger stopped resetting. Hoped it was gummed up. 
  Figured out it would rest if hammer was pulled to to half cock. Also if hammer is pulled past normal cocking position it resets. But firing or hand cycling the slide does not reset the SA trigger. 
  Disassembled the frame today. Trigger and hammer look fine. The sear shows a lot of wear. The back of the sear has a lip on it now. On the top side. And a rough edge. 
  The left front leg of sear is rounded and worn. 
  Thinking of getting an Extreme Sear from PD. Has to outlast the original. Round count is under 6,000. Almost no dry firing too. 

[Endall]

Another pic of rear of sear.

[Endall]

  Rear sear wear

[catabol3]

That seems like a lot of wear for only 6,000 rounds, wonder if they had a bad batch of seers maybe? 

 

When I had an issue with my Tanfo SA trigger not resetting it was the trigger over travel screw had backed out.  I adjusted it and was back in business.  I should have put some thread locker on the screws and it never would have happened. 

Edited March 26 by catabol3

[Endall]

  I hoped the adjustment screw was the issue. But the trigger will reset if hammer is pulled all the way back, a little past where slide cocks it. Loosened up screw anyway. 
  Assume metal used is defective. Never seen a sear breakdown with such low round count. I am original owner, had it about 12 - 13 years. 
  Ordered an Extreme Sear from Patriot Defense. Good people. Should last longer than me. 
  Sear wear was maybe an issue the last 500 rounds.  Noticed trigger felt mushy, break was still a little over 2 pounds. Thought trigger bar was gunked up. 
  There are flecks of the sear finish in trigger cage. Sear rot?

[Endall]

  Removed the original sear and installed an Extreme one piece sear yesterday. The original sear is chewed up a little. Mainly the gold coating flaking off. Saw specks of it in sear cage. 
  Cleaned up sear cage when swapping the sear. Exercised the safety a few times also.

  Hand cycled the slide 50 times today. Hammer dropped every time.  I THINK the new sear fixed it. But cleaning metal and loose coating out of sear cage may be what fixed the problem. 
 Hammer looks fine, should be, hammers are harder the sears.

[johnbu]

That malformation tells me the metal interface was too soft.  Tanfo uses soft sear and adds a surface treatment to harden JUST the surface. Thats why you dont polish the sear/hammer interface.  Yours looks like the surface treatment wasn't correct.   (Still, it lasted a while)

 

My primary gun has the extreme chromed sear.  8 years and 10-25k rounds a year plus daily dryfire.

[DenC]

Sorry to hijack, @johnbu What tanfo model is your primary? And how long did the original sear last or did you replace it straightaway?