I've got a new upper I just put together. It's a Daniel Defense upper, DD 12" MFR, DD 11.5" barrel, yada, yada.

I'm running a Thunderbeast 223A on it. With factory Winchester White Box 5.56 55gr ammo it has been 100%. Zero problems.

I wanted to see how it shot some of my 69gr SMK reloads and see how accurate it actually was. Accuracy was pretty good, but it would not reset the trigger. The round would eject and chamber a new round, but the trigger would not reset.

This lower has a Timney trigger in it, but it ran 100% with my suppressed 300 Blackout upper and 100% with the Win White Box stuff, just not my reloads.

What do you guys think? Not enough pressure? Too much? Any thoughts?

Thanks,

Dan

might be the buffer spring not allowing the hammer to go all the way back.

What is your ejection pattern with the reloads?

To be honest, I don't know for certain, but I think they were landing about 2 0'clock. Couldn't really tell you how that compares to the factory ammo except I think they were more 3 o'clock-ish.

What happens if you slowly cycle the BCG with the charging handle? Does the trigger reset?

Are you getting "hammer follow"? Sounds like the disconnector is not catching.

It seems odd that the case is ejected, without resetting the hammer. The BCG has to move over the hammer to eject the case. If you are ejecting at 2:00 o'clock, it might be overgassed with your reloads.

If the hand cycle resets the hammer, I'd suspect the BCG is bouncing the hammer off of the back swing before it can catch the disconnect ear, but JMO.

Looks like others have had a similiar issue:

http://www.ar15.com/forums/t_3_66/622967_Timney_Skeletonized_AR_trigger_problems.html

Read down in the comments section, same problem:

http://www.thetruthaboutguns.com/2011/05/foghorn/gear-review-timney-ar-15-triggers/

Thanks for the links. Might just need to swap this trigger into a non-suppressed rifle and move on.

Thought. Are you shooting it off the bench and the magazine is in contact with the bench?

I'm shooting off a bench, but I always use the 10rd Pmags when I do, so not the issue.

I had another rifle that had a Geissele in it, so I swapped them. The other rifle never wears a can, so we'll see how it all works out. Will report back after the next range trip.

Don't know, seen something similar but the gun was not picking up a new round AND was not cocking the trigger, was bolt carrier rubbing on the magazine.