SLR15 AR-15 / M-16 / M-4 / AR308 Armorer Course
When: January 14-15, 2019
Where: Appleton, Wisconsin
We conducted a 2-day (16-hour) AR-15 / M-16 / M-4 / AR308 Armorer Course at Fox Valley Technical College Public Safety Training Center in Appleton WI. We have taught numerous courses there over the last decade, and we look forward to more. The training room offers great lighting, plenty of table space for people to spread out, and a large screen which allows us to project some powerpoint and animations onto, showing close up detailed pics of gun parts, and especially when looking at finer detail things like machining, stress cracks & wear.
This class was a mix of Law Enforcement Officers from different areas of Wisconsin.
Rifles represented in this course were Colt, Bravo Company, DPMS, Bushmaster, Sig Sauer, DRMO Colt M16A1, Smith and Wesson M&P15T, Rockriver, Aero Precision, AlexPro, and a few home built guns.
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.
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: Two Officers Aero Precision rifles had no extractor spring insert. We remedied that.
Note: When checking bolt carrier keys (gas keys) for proper staking, a couple of Rock River rifles had light gas key staking where the stake was barely touching the screws on one side and not on the other, and one Officers Aero Precision had no staking. They put to use the MOACKS and Sully Gas Key Stakers that we had with us, and got things properly staked so they don't come loose.
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. At the end of the day everyone put their rifles back together, making sure that everything was in proper working order.
Day-2 started with a review of everything that was covered on day-1, with some greater details and myths covered. We then went back into trigger groups in great details, covering single stage, 2-stage, good and bad triggers, differences and options in spring systems, diagnosing problems when semi-auto turns into burst, and showing the differences in quality of triggers that are on the market. Once done with semi-auto trigger systems, we went into select fire trigger groups covering full-auto and burst trigger groups, to include replacement and diagnosing and repairs when experiencing malfunctions.
Note: One Officers Rock River had a 2-stage trigger that had been reported to be slipping and firing an occasional burst. Upon close inspection it was found to have erosion on the heel of the hammer where it contacts the disconnector. He will be replacing the trigger system.
After trigger systems, we went through the rest of the lower receivers. Everyone in this class had collapsible stocks except for one M16A1 that had an A1 stock. We covered the proper mounting & gauging, and proper castle nut staking. Everyone stripped their lower receivers, which allowed a chance for further inspections, and we went through a session on troubleshooting. 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.
Note: Two Officers from the same agency had a loose collapsible stocks that would rotate by hand. They were mounted using a Magpul ASAP plate, which uses a small locking piece that is fitted between the ASAP plate and receiver extension (buffer tube). This small locking pieces was missing, which is why the the stock systems wouldn't lock into place. (We see this a couple of times a month in classes). These Officers said the rifles were custom builds that had been built for their agency by a local gunshop. Fortunately we carry a bunch of these locking pieces that we have machined out with us, and we installed them putting things back into proper function.
We then got into a session on the timing. This is where we cover proper cycling, covering what effects timing, and how & what happens when it is out or proper time, dwell time, suppressor issues, etc, and how to get things into proper timing.
Note: This class had 5 agencies that had rifles with suppressors. Several of these agencies had been experiencing fail to extract issues, which they all attributed to just mounting the suppressors and not dealing with any possible timing issues. After we went through timing, they realize that often times the addition of a suppressor can change the timing of the rifle and it may need to be adjusted.
There were one Sig Sauer piston rifle in class. We showed how the piston system works, and how to properly maintain them and make adjustments when necessary.
The last half of day-2 was spent on the upper receiver assembly. We covered barrel removal, mounting, fixturing, gauging & inspections. We show numerous was to fixture a barrel into a vise, and our preference as to which fixtures/methods to use when and how. Two Officers took advantage of disassembly, removal and remounting their barrels. Several Officers commented that the methods we show in how to disassemble and reassemble barrels and front sight bases was much easier that they had tried on their own. 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.
Note: We covered how to mount a gas block, and how to use our gas block alignment fixtures to get the gas block in perfect index with the barrels gas port. Our gas block alignment fixture can also be used as a barrel dimpling fixture, where being able to countersink the gas block screws into the barrel so it doesn't slip out of alignment is a good thing. Dimpling barrels and countersinking gas block screws is the minimal thing that should be done, it is my personal preference to drill and pin gas blocks to the barrel, which is something we teach in our advanced armorer courses.
At the end of the day everyone put their rifles 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
Gas Systems & Piston Systems
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