CMC trigger issues

Dultimatpredator

Dultimatpredator

Well-known member
I installed my 2.5 lb competition single stage trigger in mt aero M5 lower today. It brakes at 34 oz!

The issue I'm having is there is about an 1/8 th of travel in before it brakes. If I put the safety on and try to engage the trigger it will travel a good 1/8th of an inch and make a clicking noise when it hits the safety. I can move it back and forth like the video I have linked. The video is not my trigger. So when I take the safety off and pull the trigger there is the same amount of travel or more...sometimes a 1/4" inch before the trigger brakes. I called CMC and they're going to send another trigger to try. I have a bad feeling it's going to do the same. The housing itself is not moving. There is a gap between the end of trigger catch and the safety selector switch causing the slop. CMC said it could be the trigger, the safety selector, or the hole for the safety selector switch milled in the wrong place.

Well, I removed the trigger and can wiggle the trigger mechanism back and forth and it's making the same clicking sound with the same amount of play.

If I pull the trigger while it's on safe it takes up all the travel so when I flip the selector to fire it's a crisp brake....well I'm not going to obviously do this every time.

Anyone else run into this. Would an adjustable safety selector switch fix this? I'd hate to spend another $60 on an adjustable selector when I can just exchange it for a 3lb timney for another $40... The only bad thing is the timney isn't rated for an AR10 where the CMC is. I'm shooting a 243 so I probably won't ever have issues detonating prImers.

Here's the link of someone else having issues with the same trigger and in the links below three were a few others.




I'd like to fix this as it has a nice light pull. My 3lb timney brakes at a consistent 40 oz in my POF so worse case senario I'll exchange it. The CMC wasn't consistent as far as pull weight goes when I tested it. It mainly pulled at 34 oz but every couple of pulls it jumped up to 36-40 oz then back down to 34oz.
 
Last edited:
The ones I have exhibit similar characteristics which I like. Initial pull is close to speck at a couple ounces over 3 lbs. with no discernible creep. Gives and added amount of safety being a little heavier when carrying or letting someone else use it. But when I set down with the safety on I can "set" the trigger as I call it by pressing it and it moves slightly back and kind of clicks. I now have an approximately 2 lb. 10 to 12 ounce trigger with no creep. I know you would think that creep would be there if you would not do this but I cannot detect it and I am use to pulling a 1lb. 14 oz. trigger on an open 38 super pistol for decades in open class as an M class shooter. The trigger stays at that sub 3 lb. pull on all subsequent shots. My 2 cents.
 
That is bizarre. The CMC I just installed doesn't seem to do that at all. The trigger does move a tiny bit when the safety is on, but the pull doesn't feel discernibly different when I flip the safety off and fire.
 
According to their CS dept I believe they machined too much metal off the trigger where it rests under the safety selector switch. It was the the only part of the trigger that had a bright chrome polished appearance so it made sense that CMC got a little happy with the machining and removed too much surface area. Sounds like it's pretty common with CMC triggers the more I research them along with the trigger not resetting. Google CMC trigger issues and you'll find tons of complaints and problems with them. There is a reason they have been the price leader drop in trigger for years up untill rescently. I sure it's a great trigger if you get a good one. It was nice and light but as I stated before the pull weight was very inconsistent. Maybe it was caused from 1st stage travel is not sospose to have since it's a single stage trigger. I learned my lesson and blowing some more dust off my wallet for the timney. Never had a problem with all the other timneys I have installed in my 700's and AR so ill roll the dice and hope it will ignite heavy military primers (if I ever use them)in my AR10.
 
Last edited:
Replacement CMC showed yesterday direct from CMC. Figured I'd try it before I sent it back to them since I returned the first one to exchange it for a timney. The 2nd one has the same amount of travel as the first and can be moved back and forth when the safety is on just like my first one and like the one in the video posted above. It has a good 1/4" of travel...or creep as some say, before braking just as the first one did. Guess there is no such thing as a CMC single stage trigger. With all the creep it feels like a soft sloppy pull. I never measured the pull but I could tell it has heavier. I boxed it back up and returned it to them. If this is a single stage trigger I'd hate to see how much travel their 2 stage triggers have.
 
Last edited:
If I didn't have bad luck I'd have no luck at all. The timney showed today. The three pound trigger is closer to 4lbs. It's 56 oz to be exact and has more travel than the CMC trigger.
 
Back
Top