SLR15 Rifles AR-15 / M-16 / M-4 ARMORING COURSE
When: May 11-12, 2015
Where: La Crosse, WI Police Dept
We conducted a 2-day (16-hour) AR-15 / M-16 / M-4 Armorer Course at the La Crosse Police Department. This was our second course here, and we look forward to more. The training room with plenty of table space, decent lighting, and a screen that we were able to project 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 a mix of Law Enforcement and Nuclear Security from Wisconsin and Minnesota.
Rifles represented in this course were many, to include DPMS, Colt, Bushmaster, HK, Rockriver, Smith & Wesson, POF. LWRC, Primary Weapons Systems, and a couple of custom builds.
Day-1 started with going through the course manual and tools that we supplied to everyone. Everyone was shown the tools in front of them, and what they are for, and that these will do about 95% of the work on their rifles (short of restocking and rebarreling, of which wrenches and sometimes fixtures are necessary). We also supplied everyone with a sampling of 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 walked through our recommended procedure for field stripping a rifle, and why 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 what fouling does, and our method for removing it.
We went through the entire bolt carrier assembly, which included inspections, maintenance, upgrades, 3 types of gas rings, differences in finishes, machining, etc. We had several students that gas keys that needed to be staked better, of which we supplied several of the MOACKS tools that were put to good use. While inspecting bolts, we had a Colt 6920 bolt that had a broken ejector spring, this was replaced.
During the afternoon session, we went through the lower receiver assembly. Everyone in this class had some type of collapsible stock, so we went through mounting & gauging, and staking. Several rifles had to be re-indexed, and staked. The lower receivers were disassembled. We went through the fire control group, to include detailed inspections of all the sear engagement surfaces, spring types, single stage, and two stage trigger systems.
We had a Rockriver that had a broken trigger pin, this rifle showed signs of it cycling too quick, which means that the rifle was beating itself up, so the trigger pin was replaced and a new action spring was installed.
There was one student that had one of his agencies DPMS full auto rifles with what appeared to be a large headed pin holding the hammer in. The lead armorer for this agency was present in class, who stated that this rifle belonged to one of his Officers, and the hammer pin kept coming out, so in his farm yard fixing experience made a custom pin and put it into place, then smashed the heads down so you couldn’t remove it. The lead armorer decided to remove it, so we supplied him with a file and he removed one of the large heads on the end of the pin, then removed it. It was found that this custom wide headed pin was actually a common house nail. The house nail didn’t create a tight fit, so as this hammer cycled it wollard-out the right hammer pin hole on the receiver to the point the hammer is now wobbling. It was determined that the hammer had a broken J-spring, which is why the hammer pin kept walking out. Both the hammer, and hammer pin were replaced.
The end of the day was spent with going through in great detail the eight cycles of fire, proper timing, .223 vs 5.56, different gas systems, etc
Day-2 started with a review of everyone that was covered on day-1, and we went back into proper timing on the gun. We covered proper timing, cycles of fire, showed what effects timing, how & what happens when it is out or proper time, dwell time, suppressor issues, etc.
We went back into the lower receivers. We went through machining on parts and receivers, showing examples of good & bad, and how this effects the entire rifle. Once factory machining was covered, we then showed where people alter trigger systems by doing a trigger job, both good and bad, and covered whey we don’t recommend that people do a trigger job on a work rifle. We then went through full-auto, burst, and illegal street conversions. Lower receivers were then reassembled for the last time, inspected, stocks indexed with the castle nuts staked, and everyone made sure everything is in proper working order.
After lunch we went through the entire upper receiver assembly. There was one piston rifle present, so we showed in great detail how these work, and covered troubleshooting and stress on these. We went through barrel removal, mounting, gauging & inspections. Everyone was allowed to rebarrel their rifles or make adjustments. Everything was gauged, and we had several rifles and were improperly mounted. This improper mounting was causing premature wear & stress, of which these rifles were fixed before they left the class. When inspecting barrels that had been removed, none of them had been put together to the Milspec from the manufacturer. Every barrel that was pulled, was remounted to Milspec, torqued, and properly indexed.
One agency had a Surefire suppressor on a rifle that had come off when shooting, and when it came off during that string of fire, the suppressor was accidentally shot, causing a large hole in it of which made it inoperable. This same agency had several SWAT rifles from DPMS & Rockriver that were taken out of service due to no longer being able to shoot a decent group anymore, reports of 9”-15” at 25yds, and several bullets keyholing. A very close look inside of these with a borescope, showed damaged crowns from improper cleaning, heavy erosion at muzzle & throat, and heavy pitting from using copper solvents improperly. These barrels were supposed to be chrome lined according to their staff, but looking through the borescope showed that there was no chrome lining. These barrels had eroded to the point that the bullets were also striking the baffles on their suppressors. This agency has decided to rebuild these uppers with new barrels and bolts. We helped them remove the Surefire suppressor mounts that had mounted using Rocksett, and now these can be used on their new barrels.
At the end of the day, everyone reassembled their rifles. A function test was done to ensure everything was in working order prop. Everyone did chamber inspections, checked & gauged the four gas seals, gauged firing pin protrusion, measured the trigger press, and headspace.
Weapon Notes: We had a Colt LE6920 with a broken ejector spring, and a Rockriver with a broken hammer pin. A student had a DPMS full auto rifle with a wollard-out hammer pin hole due to a customized common house nail that we being used for a hammer pin.
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
Nomenclature
Identification of Group Components
Semi, Burst, and Full Auto Parts and Conversions
Complete Armoring Disassembly / Assembly
Barrel Replacement
Cleaning and Maintenance
Sight and Distance Considerations
Ballistic Issues
Barrel: Twist, Length, and Profiles
Gas System
Parts Interchangeability, including Brands
Headspace
Firing Pin Protrusion
Trigger Jobs
Chamber Inspection and Issues
Troubleshooting, diagnosis & repair
Gauging, Inspections, Stress & Interval Issues
Accessories and Customizing
Tool Options and Selection
Iron Sights
Optics
SOP/MOD Accessories and Additions
CY6
Greg Sullivan "Sully"
SLR15 Rifles
TheDefensiveEdge.com
(763) 712-0123