Direct impingement AR rifles require good amounts of cleaning and lube. Apply CLP to the bolt after a cleaning to make sure the rifle runs smooth.

Click! A sound that has long brought sweat to the brow of even the most seasoned operator, second only to that of an equally unintended bang! In the first instance, the firer has acquired his or her target (often under the duress of combat), only to be sorely disappointed with the failure of his or her weapon to discharge. Conversely, in the second instance, the weapon has fired prematurely, either by operator error or through mechanical failure. Preventing such catastrophic cases from arising due to mechanical failure is the purview of factory-certified law enforcement and military armorers.

It takes the uninitiated only a quick glance at today’s headlines to see the need for protection from such preventable liability. Case law abounds pertaining to agency failures to properly equip and train their respective law enforcement personnel, and the jury awards that have arisen from those types of cases could prove fiscally unrecoverable for a small municipality or police department. Perhaps equally important is the safety of those who are sent into harm’s way. There is simply no room for questions when stacking a door, making a vehicle stop, or assaulting an objective—the weapons simply must work as advertised, or lives (and careers) may potentially be lost.

Colt Advantage

I was recently invited to attend the three-day Colt Defense Armorer’s School, hosted by the West Hartford (Connecticut) Police Department. This course curriculum consisted of the complete disassembly and reassembly of almost every type of military and civilian AR platform of Colt manufacture, to include those equipped with fully automatic and three-round burst trigger groups. Detail inspections, troubleshooting, maintenance, parts compatibility, unauthorized modifications, gauges, and the application of a wide variety of commercially available armorer’s tools were also covered in great depth.

To be fair, there are many aftermarket resources for AR-related training; however, some offer questionable practices and somewhat dubious or conflicting information. Online videos and blogs pertaining to the assembly of the AR platform are readily available, and the availability of aftermarket parts and accessories is unquestionably at an all-time high. Although even a novice shooter wielding a screwdriver can certainly affix many accessories, this is strongly frowned upon (and often completely prohibited) by many law enforcement agencies and the military. The reason is simple: There is no foolproof way to determine parts compatibility, functionality, or interchangeability between the offerings of so many manufacturers without extensive (and costly) testing of each potential assembly.

Colt rifles have served for decades. A lot can be learned on the battlefield and this experience is carried into the classroom.

Although the mil-spec label is certainly enticing, most parts still require proper assembly and function testing in order to work properly in a specified application. According to Colt, the systems and parts it manufactures have been subjected to extreme military testing and evaluation regimens, and have been determined to offer the end-user some of the most time-tested, durable, accurate, and functional firearms available.


Day one of the course consisted of introductions between the instructor, a 30-year veteran of a large municipal police department, Colt employees, who were on hand to assist with any issues pertaining to law enforcement sales and support, and the students themselves. Course attendees were mostly state and municipal law enforcement officers, who were attending while in a duty status, as most had already been tapped to perform said duties for their respective agencies. The several remaining students were members of the military, corrections, and nuclear power plant security officers. This course is strictly restricted to the categories mentioned above, as it fully addresses the inner workings of automatic sears and trigger groups, which is considered to be restricted information.

An armorer inserts a dummy round into an M16A4 to ensure the weapon meets specifications.

Following the introductions, the instructor covered the history of the M16/AR-15, and Colt’s involvement in the continuing development of that weapons system, which also covered theory and internal ballistics. He then directed each student to obtain a set of armorer’s tools and a gun case, which contained one of 30 or so assorted weapons available for student use. These weapons ran the full spectrum of the AR family, ranging from Colt HBARs, M16A4s, 9mm SMGs, and M4s with either full-auto or three-round burst trigger groups. Also covered were the newest Colt LE6940 and LE6940P models, featuring monolithic uppers and, in the case of the latter, short-stroke gas piston systems. Students were then instructed as to the proper way to clear, inspect, lubricate and perform function checks with each weapon before disassembly began.

Disassembly was a step-by-step process by which the instructor would demonstrate the proper method for taking apart each sub group, and then the students would repeat the assigned task at their own workstations. This process of demonstration and repetition continued during the next two days, with each new step incorporating those just taught and adding an additional task. These lessons were interspersed with classes on firearms theory, manufacturing processes, and historical data. At times, it became a rote process; however, the instructor kept the course lively with tasteful humor and personal anecdotes, and by the end of day two, each student could easily disassemble and reassemble the weapon system as a whole. For several, this was the first time they had ever completely disassembled or reassembled an AR in their entire careers.

A U.S. Marine Corps armorer demonstrates removing the upper receiver of an M4 Carbine, an easy step after making sure the rifle is safe and unloaded.

On day three, additional troubleshooting topics were covered, along with more in-depth maintenance of the entire system. The culmination and certification exercise consisted of a written exam, followed by a the complete disassembly of the AR-15/M16, a thorough jumbling of the assorted parts, pins, and springs for each weapon, followed by a complete reassembly and functions test. With the students easily accomplishing these tasks, the instructor then inspected each weapon thoroughly before the student was given a graduation certificate.


The duties of an armorer are not for everyone, and the job description is similar in concept to that of an airplane mechanic or a parachute rigger. The tasks are often repetitive, however, they require a particular attention to detail that not everyone possesses. For that reason, I highly suggest that only those who truly aspire to take on the responsibility of maintaining lifesaving equipment apply.

So, why attend such a course? Well, the answer was fairly simple for me: I can now safely work on Colt platforms, and I can ensure that the weapons that I work on and inspect are safe and functional for official carry, as well as for competition and home defense. This training is also legally defensible, provided that all work is accomplished using authorized Colt parts, procedures, and installed upon Colt firearms by qualified persons. Colt’s armorer certification is good for a period of three years, at which point a refresher course is required for renewal.

Colt armorers demonstrated tearing down the bolt on an M4 Carbine. Along with the proper techniques, students can also learn how to use the right tools.

Along with the exceptional quality of the instruction given, I also found the Colt CM118 Armorer Manual to be an excellent companion product, featuring not only the most current line of firearms and parts produced by the company, but also listing Colt legacy parts that the armorer may come into contact with during his or her career. Sequential, color photographs clearly walk the armorer through each step of the required processes, and serve to jog the memories of those who do not perform this level of maintenance on a day-to-day basis. This standalone document is a must-have for any professional AR or M16 armorer, as it covers the width and breadth of current Colt doctrine. That being said, this manual is only offered to qualified students or graduates of the Colt training, and is yet one more great reason to attend. Find out more by calling 800-241-2485 or by visiting

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