Triggertech Diamond/ Impact 737R Delayed Firing

LongShotTV

Private
Minuteman
Jan 17, 2025
2
2
North Carolina
HI folks, at a PRS match this last weekend there was about 5 shots out of 200 where I swear it felt like I shot a muzzleloader, and got a slightly delayed bang after hearing the trigger click. I cannot replicate it by dry firing at my bench back home.

I also recently worked up a new load for my 6 creed, the gun started speeding up and I backed off the load a bit, putting 37.8 gr of H4350 in with a berger 109 hybrid. The load shot really tight so I didn't think anything of it. But now I am wondering, should I be looking at the trigger, or could I possible have such low case fill that I got delayed shot/hang fire? I use CCI450 magnum SRP so afaik the primer needs just enough uumph to push the bullet out and start burning the powder, but while I feel confident at reloading I've never really gone down the case fill rabbit hole, and since this is a new load and the trigger only has ~1200 rounds on it, I am wondering if this could be the problem instead.

Silver lining, I flinched before the shot went off every time, so now I know I need to work on my follow through 😅

Thanks all!
 
  • Haha
Reactions: ShtrRdy
Have you removed the firing pin assembly and checked for interference? For example there could be build up of oil or grease. Or the firing pin spring could be dragging inside the bolt body.
 
  • Like
Reactions: D_TROS
Three or more years ago, there was a run of TriggerTech triggers which did this.

Return the problem trigger and they will ship you a new one as soon as they have notice yours is on the way back to them. That’s what they did with mine.

Good luck.
 
I have the issue with small rifle primers and creed volumes too when it’s not a super hot load. It’s why I default to large rifle creed brass now myself.
It has been in an action with a tt diamond though… but step it up from <38 to >39 and no hang fires.
 
Had two separate TT diamonds do this over a period of a year. Both on 737 actions. I was shooting several hundred live rounds a week and tons of dry firing. It first happened in a match but I could make it happen in dry fire if I was INCREDIBLY gentle to the trigger on press. I would feel the various sears release but the top sear wouldn’t….until it suddenly did. Never had a pierced primer or a load of powder dumped into the trigger or cleaned without a bore guide. Went through the recommended cleaning and testing from TT support. They did replace both triggers under warranty. I lost confidence in TT and switched to BIX. It’s the trigger, not your load or the action, in my opinion. I vastly prefer something I can take apart and clean, inspect and adjust.

ETA, I did move the triggers around to various actions and switched bolts around between three different 737s and the common element was the trigger.
 
  • Like
Reactions: D_TROS
Thanks all, very helpful. Definitely going to take the firing pin out and clean it out, sounds like a good thing to do anyways. Will swap out the trigger since I have another lying around and see if that fixes it for now.

On a side note, learning that I have a carbon ring that was causing pressure increase, which is why I dropped the load way down. Going to take care of the carbon ring and probably push back to 38.5-39 gr of powder which should get me back to where I was before this ever happened.
 
  • Love
Reactions: ShtrRdy