SLR15 Rifles AR-15 / M-16 / M-4 Armorer Course
When: August 6-7, 2018
Where: Manchester, Connecticut
We conducted a 2-day (16-hour) AR-15 / M-16 / M-4 Armorer Course that was hosted by the Manchester Police Dept. This was our first time doing a course at this location, and we look forward to future ones. The training room offered plenty of table space, decent lighting so people could see small parts, and was equipped with a HDTV system that allowed us to show animated graphics of the weapons system, powerpoint detailed pics of gun parts, and especially when looking at finer detail things like machining, stress cracks & wear.
The student base was all Law Enforcement Officers from different agencies from Connecticut, Rhode Island, and Delaware.
Rifles represented in this course were Colt, Stag, Primary Weapons System, Daniel Defense, Bravo Company, Ruger, Bushmaster, LWRC, Rockriver, Sig Sauer, Windham, Smith and Wesson, and a few custom builds.
Day-1 started with going through the course manual that all students are given. Students were supplied with their own set of basic tools that are necessary to do 95% of the work on their rifles (short of restocking and rebarreling, of which wrenches and sometimes fixtures are necessary), Slip2000 "EWL" Extreme Weapons Lubricant and #725 Cleaner Degreaser, etc. A short session of nomenclature was covered, at which time covered every feature and exterior piece of the rifle to include all the hidden design features that most people are not aware of, and everyone prepped the rifles for disassembly work. Everyone was taught the procedure series of checks that we recommend. There was also a discussion on other lubricants and where problems can happen if they freeze or get gummy.
Everyone was taught our recommended way to field strip a rifle, and whey we do it this way so as not to cause damage, premature wear or stress on anything. We covered maintenance of where and what to clean, and what needs lubrication to keep it running. We showed why not to use the firing pins as tools. We showed everyone our recommendation of how to remove fouling and why, and everyone got to use our methods.
The entire bolt carrier assembly was covered, to include inspections, maintenance, upgrades, 3 types of gas rings, and differences in finishing and machining. carrier key (gas key) installation and staking, ejector systems, etc. Everyone was introduced to the different types of gas rings. We went through what each types does, and their proper installation order.
Note: This class must have a little ADD/ADHD, as the last time going through the bolt assembly, it seemed like an epidemic of people launching ejectors and not following directions, so many of them had to assume the armorers position on the floor. Once we beat some sense back into everyone, they were back on track and were able to complete the task at hand.
Note: There were also two bolt carriers from Ruger, and 2 from Anderson and 1 from Palmetto that didn't have any gas key staking, and several carriers from Bushmaster & Rockriver that had very light carrier key staking, where the stake marks weren't even toughing the screws. These Officers used the MOACKS and Sully Gas Key Stakers that we had with us, and made the corrections.
We got into the lower receiver assemblies, starting with the fire control group (trigger group). We teach this in a building block format, starting with baby steps of getting things out and in, then build into how things work. Everyone learned how to install and remove things so you don't cause damage. We went through detailed inspections of all the sear engagement surfaces, spring types, single stage, and two stage trigger systems. The last part of the day we spent on an introduction to timing, which we like to do so that it grows in peoples brains over night, in preparation of getting into great details of timing for day-2. Everyone put their rifles back together, making sure that everything worked properly before we ended the day.
Note: One agency brought 3 problematic rifles to class where the safety selectors were hanging up. Upon inspection these were all DRMO M16A2's that someone had put semi-auto trigger/hammer/disconnectors into, but kept the full auto safety selectors. The full-auto safety selectors were removed, and I gave them new semi-auto safety selectors, which got the rifles working correctly.
Note: Another agency brought 4 DRMO M16A2's to class, which had burst trigger groups in them. Someone from their agency had bought DPMS semi-auto hammer/trigger/disconnector conversion groups for them to convert them to semi-auto only. Upon inspection of the conversion parts they brought, there were to springs. Which they learned that the burst hammer spring isn't compatible with a semi-auto hammer. I offered them springs, which they declined and left the burst trigger groups in, stating that they are going to talk to their administration and try to get them to put these particular M16A2 with the SWAT Team, and then transfer some of the semi-auto SWAT Teams rifles to patrol. They learned at least that someone at their agency didn't know anything about what they exactly needed to make correct conversions to semi-auto only, and if they are going to make the conversion then they will need to obtain the correct springs.
Day-2 started with a review of everything that was covered on day-1, with some greater details and myths covered. We then got into a session on the timing as it pertains to proper cycling, and showed what effects timing, and how & what happens when it is out or proper time, dwell time, suppressor issues, etc.
Note: Several agencies had added suppressors from various makers to their rifles. All of these were baffle type suppressors. This let us to the discussion of how to properly mount suppressors, to include direct thread vs mounts (My preference is a mount). We also showed how suppressing a rifle will change the timing, and how to properly set up a rifle for maximum performance suppressed.
There were were several piston guns in this class from Sig Sauer, Ruger, LWRC, and Primary Weaspons System. We showed several examples of piston systems, and their personality traits. We showed how these work, adjustments of when/when not to adjust, and covered what the pros/cons are, and covered detailed maintenance of why/where/when. There was one piston rifle from LWRC in class that had about 8K through it, which allowed people to see erosion issues on the piston system.
Everyone in this class had collapsible stocks, and we showed the proper mounting & gauging, and made sure everything was properly staked. Everyone stripped their lower receivers, which allowed a chance for further inspections, and we went through a session on troubleshooting. We showed examples of good & bad machining on parts, and how this effects the entire rifle. Lastly we went through full-auto and burst systems, showing how these work, and trouble shooting related to such. Once everyone was comfortable with the entire lower receiver assembly, the were put back together, inspected, and made sure everything is in proper working order.
The last half of day-2 was spent on the upper receiver assembly. We covered barrel removal, mounting, gauging & inspections. Everyone was allowed to rebarrel their rifles or make adjustments. We showed why people should be picky on how barrel nuts are indexed, and why there is a torque spec. If barrel nuts are not indexed properly, it could cause stress and premature wear during cycling and excessive wear on the gas or piston system. If barrel nuts are not torqued to their minimum recommended specs, things can come loose, and if it's loosed you can lose accuracy, being loose can also be a safety issue.
Several Officers took advantage of the time & tools, removing their barrels. Upon inspection of the barrels that were removed, none had moly paste, and several of the barrel nuts were not properly aligned, and one was loose as if it was never torqued to proper spec. All barrels that were pulled, were remounted, torqued and properly indexed.
Note: One agency brought a new DRMO M16A1 that had been converted to semi-auto, and had a 16" M4 upper receiver assembly put on it. The Officer brought it to armorer class, as their agency had sent it with an Officer to a rifle instructor class the week prior, and the rifle was a single shot. The Officer explained that it could be loaded, press the trigger and it fires, but it will not unlock, but then you could manually cycle the action and repeat. The first thing I had the Officer do was remove the gas tube, and inspect that the gas tube was clear to allow air to pass through it, and that it wasn't installed upside down, and upon inspection air would pass through the gas tube, and it was installed correctly. So we removed the front sight base on the barrel, and found that the barrel had no gas port drilled into it. The barrels markings indicated that it was from DoubleStar. We reassembled the barrel, and the Officer was advised to get into contact with Doublestar and put it into their customer service departments hands.
Once all the rifles were put back together, everything was inspected and gauged to make sure it was in proper working order. Everyone did chamber inspections, checked & gauged the four gas seals, firing pin protrusion, trigger press, and headspace.
Here is a brief overview of a few things that were covered:
History of the Weapon
Cycles of Function
General Disassembly & Assembly
Identification of Common Problems and Parts
Identification of Group Components
Semi, Burst, and Full Auto Parts and Conversions
Complete Armoring Disassembly / Assembly
Cleaning and Maintenance
Sight and Distance Considerations
Barrel: Twist, Length, and Profiles
Parts Interchangeability, including Brands
Firing Pin Protrusion
Chamber Inspection and Issues
Troubleshooting, diagnosis & repair
Gauging, Inspections, Stress & Interval Issues
Accessories and Customizing
Tool Options and Selection
SOP/MOD Accessories and Additions