Hiperfire 24 3G Trugger Issues

[Wvaughn7]

I recently put a Hiperfire 24 3G trigger in an NFA lower running Glock mags. I shot my first match since the change today and had two different stages the trigger did not reset on one shot. My bolt is cycling well past the reset point of the trigger and neither time it happened did the load feel like it could have been light and not cycle the action completely. What I don’t understand is why I am having a 1 out of 100 or so reset issue. Has anyone seen this or have any suggestions to remedy it? The trigger only had about 200 rounds on it when it happened. 

[hitman]

Is there any movement on the pins?

[Acer2428]

I had an issue w/ mine where it wouldn't reset after the FIRST shot only, but was fine after I manually racked it and went from there. I can only assume it was a safety interaction issue, but I took the spacer/pad out of my taccom recoil assembly and it ran fine. What's your buffer spring/spacer, etc. setup?

[Wvaughn7]

I have not checked for movement of the pins but they are the supplied pins that came with the trigger. I am using a standard carbine length 7.5 ounce buffer with 5 quarters behind it. Cycling the action by hand resets it every single time with 7 quarters but I liked the recoil of 5 better, so I should have plenty of bolt travel. I can take a couple out and see if my issues go away. 

[Gregg K]

If you are like most of us using HyperFire triggers you installed the heaviest hammer springs to get the lightest trigger pull. The extra pressure it takes to reset the hammer with the heavy springs may be slowing your bolt down to where it doesn't cycle as far back on occasion. You may have to retune your buffer system to make up for the change. You could try putting in the weaker hammer springs to test. Maybe lighter buffer, less quarters or lighter buffer spring.

[Wvaughn7]

Yes I do have the heaviest springs and I was going to try the medium ones. When I put the trigger in I removed the weight in the boot as well so that should compensate for the heavier hammer spring pressure. I probably won’t put any number of rounds through it until the end of the month but will make sure to update you all. 

[chevrofreak]

Lighter springs help, but my girlfriends PCC still fails to reset from time to time. 

[stick]

Try taking out all of the quarters.  or take out one at a time and see if the issue persists.  I had a trigger reset issue with my 24C, but it was only after I installed the short stroke buffer kit.  I had to remove the delrin spacer in the back of the buffer.

[lee blackman]

There are three things I can think of off the top of my head that will cause this issue. 

 

The first would be out of spec pattern holes (or a defective hyperfire).  Overlapping tolerance issue could contribute.  Simple solution would be swap out the whole assembly with another and see if you have the same problem. Just for trouble shooting purposes.  You said you have one in another gun right?  I also recommend a set of KNS anti-roll pins, and a noveske 60 safety.  The polish stainless surface of the anti-roll pins, and the hard slightly large milled tumbler of the noveske safety as opposed to cast traditional safety really seem to change the break of the trigger and takes the slop out.

 

The second, and this has happened to me, is you have a piece of primer floating around your receiver in the trigger group somewhere.  SImple fix, involving an air blast and visual inspection.

 

The third and probably the worst, is that your bolt carrier group isn't pushing the hammer all the way down as it travels back, and its right on the edge of the reciever gap between the upper and lower.  This means that as things flex and bounce, there is that occasional point where it won't go home.  My solution, either change to a different trigger, or change the bolt.  Anyway the important thing is to trouble shoot to see if this is the actual issue.  Next time this happens, don't touch anything, just see if the safety will move to the safe position.  If it doesn't that means that the hammer followed the bolt, and didn't cock.  If the safety will activate, it means the hammer is all the way to the rear, and everything else is working good, but the trigger spring itself does not have enough lift to reset the trigger, and it sits in kinda limbo.  You can push the trigger forward with your finger and it should reset.  If this is your problem replace the trigger spring, or at least double check to make sure its not broke, or improperly installed.

 

Best of luck,

Lee

[Wvaughn7]

I hand cycled the gun last night a couple hundred times in dry fire and I had the issue one time. When it came up I was able to diagnose that the trigger is in fact down on the bolt and not in the cocked position. I tried to replicate the problem and the only way I can do it is to happen again is to short stroke the bolt ever so slightly. I am shooting a fairly light load so maybe a slight undercharge will cause this issue. My buffer is fairly heavy and the bolt even with the weight removed is similar to many others I have seems posted so I may try dropping to a 5-6 ounce buffer to ensure a cull cycle. That and adding a tenth to my current charge.