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View Full Version : ALG QMS Trigger



Eric
25 October 2012, 19:36
ALG Defense (http://www.algdefense.com/) is an offshoot from Geissele Automatics (http://geissele.com/index.aspx). Geissele has been manufacturing high-end triggers that have a proven track record in combat and competition applications. However, these triggers might not be what all shooters need or can use, depending on the specific requirement. A mil-spec type trigger might fit the bill instead and this is where the ALG QMS (Quality Mil-Spec) trigger might be appropriate.



1. Performance Advantages for the Shooter
• The ALG Defense QMS trigger pull is smoother than a
stock trigger. This is accomplished by honing the sear
surfaces smooth while not removing metal below the
valleys of the stock surface finish.
• Sear geometry has not been changed from
standard so the high reliability that the stock trigger is
known for is unchanged.
• Trigger and hammer are made from true 8620 alloy
steel military specification castings, correctly carburized,
quenched and tempered for high surface hardness.
• Disconnector is 1070 High Carbon steel properly
Austempered into the spring range of hardness
• Springs are corrosion resistant and meet military
specifications.
• A full force hammer spring is used for positive ignition
of all type of ammunition.
• Trigger and hammer pins are improved over stock mild
steel by using 4140 Chrome-Moly steel that has been
quenched and tempered. Pins are centerless ground to
a fine finish and a diameter 0.001” larger than stock to
reduce play in the trigger assembly while retaining a slip fit
into the weapon lower receiver.
• Pull weight is above the U.S. Military minimum pull
weight of 5.5lbs but does not reach near the upper limit of
9.5lbs. Generally, the pull weight is about 6.5lbs.

2. Advantages for the Armorer
• The ALG Defense QMS trigger is an enhanced
standard trigger so maintenance and installation procedures
are unchanged.
• There is spare parts commonality between the QMS
and stock triggers
• Trigger assembly parts may be interchanged between
triggers, there are no matched sets.
• Since it is a trigger meeting the U.S. Military trigger
specifications for the M4 Carbine, the ALG Defense QMS
can be substituted for lower performing stock triggers while
still staying in compliance with Unit or Departmental
requirements.


I figured that for $45, I would give the QMS a try in a Colt 6920 that had a mediocre trigger. The stock trigger had a bit more creep and grit than some of my other standard triggers, but wasn't the worst I have encountered.

http://img.photobucket.com/albums/v503/AR15forme/Triggers/IMG_18601.jpg

Installation is accomplished just the same as any other fire control group. Follow the installation instructions. (http://www.algdefense.com/include/pdf/ALG-QMS-Instructions.pdf) Included in the kit is a hammer (rounded, no notch), trigger, disconnector, springs and pins.

http://img.photobucket.com/albums/v503/AR15forme/Triggers/IMG_18541.jpg

The FCG group has the appearance of just about any other. The sear surfaces on the trigger and hammer are honed, but excessive material isn't removed. Geissele knows more about triggers that just about anyone, so I'm sure they have a clear understanding of how much honing can be safely done.

http://img.photobucket.com/albums/v503/AR15forme/Triggers/IMG_18651.jpg

The QMS trigger dropped in just like any other. The trigger pull was a bit smoother, had a bit less creep, but wasn't really that dramatic of a change from the Colt parts. It reminded me of a well broken-in mil-spec trigger. Keep in mind, this is based on just my sample of one. I totally understand that the QMS is designed to be a tuned mil-spec trigger, but I have a couple stock trigger groups that are about the same as the QMS.

http://img.photobucket.com/albums/v503/AR15forme/Triggers/IMG_18671.jpg

As a side note, I tried an ACT (ALG Combat Trigger) which is basically a QMS trigger with a nickle boron finish. It was noticeably smoother and lighter than the QMS, but was not in stock when I placed my order several months ago.

The QMS isn't a bad mil-spec trigger, but I would not bother replacing an existing mil-spec type trigger unless it was fairly crappy. If starting a new build, the QMS or ACT trigger would be a good choice. The QMS in my rifle has been in place for about 7 months, has a couple thousand cycles on it and remains about the same. There have been no reliability issues.