CMC Drop In Trigger

Chip McCormick has been around since 1986 when he introduced the Shooting Star line of magazines for the 1911 platform. Over the years CMC has manufactured numerous parts for the 1911 pistol, and AR rifle. When I saw that a line of AR triggers were being produced under the CMC name, I jumped at the chance to try one. The CMC trigger comes in a rather novel self contained cartridge. Rather than having three major pieces like a typical GI trigger, the CMC wraps those pieces in a stamped stainless shell and rivets them in place. This means that there’s far less room for the trigger to wiggle or move. The shell fits snugly into a mil-spec forged lower. There’s no way to take the trigger apart, and there’s no way to adjust it, however, for me, that’s really not a concern. The trigger I received is a 3.5lb Tactical Curved Single Stage Drop In kit. It came with the trigger unit, two oversized pins, and a pair of Jesus clips to prevent the pins from walking out.

When it arrived I immediately sat down and installed it.

First, the upper should be removed from the lower, and all ammo should be removed from the area. I also had to remove my BAD Lever

Before punching the pins out, I set the lower on a roll of duct tape to provide a place for the pins to go.

These two pins must be punched out to remove the fire control group. This pin should be punched first

After removing the first pin, the hammer will slide out.

The second pin removes the trigger and disconnector.

At this point the grip and safety will need to be removed. The safety detent is located under the grip, and is small and easy to lose.

The CMC Trigger as it comes in the package.

Here you can see the difference in shape between the GI hammer and CMC hammer

The CMC Trigges come with oversized pins to ensure a tight fit and Jesus clips to prevent the pins from backing out.

The unit is a nice snug fit.

The pins are driven back through the trigger group and receiver. The pins are over sized and will require a few firm taps with a brass or plastic mallet.

once the pins are in place, a simple pinch with a set of needle nose pliars will snap the clips into grooves on the pins.

The safety is replaced, along with the detent.

The safety detent spring slips into the top of the grip.

The easiest way to reinstall the grip is upside down. Line the detent and detent spring up, slide the grip into place, and tighten the bolt inside the grip.

I am very impressed with this trigger. With five pulls on a scale, each pull read 3.75lbs, making this a very consistent pull. The trigger has no pretravel. The break is very clean and smooth. Over travel is nearly nonexistent, though it is there. The trigger travels maybe .050”. The reset is both easily felt and heard, making it very easy to confirm that the trigger is ready to be squeezed again. After about 1000 rounds through the rifle with the CMC trigger installed, there were zero trigger related failures, and the trigger’s pull has not increased an ounce. I’m extremely impressed with the trigger.

Compared to the Timney and Geissele triggers I have experience with, I’d say the CMC is every bit their equal. I love this trigger as much as I love McCormick’s Shooting Stars. The fact that these things are made 100% in Texas helps, too. This is my new go-to trigger, though I may choose to try their flat trigger offering at some point.