AAR SLR15 Law Enforcement Shotgun Armorer Course, Douglas WY


When: December 8-9, 2016

Where: Wyoming Law Enforcement Academy, Douglas Wyoming

We conducted a Law Enforcement Shotgun Armorer Course at the Wyoming Law Enforcement Academy. This course was held on the days 4-5 of an Armorer Week that we have been doing at this location for several years. During the week we also did a 1-day 1911 Pistol Armorer Course, and a 2-day 2-day AR15 / M16 / M4 Armorer Course. The onsite facilities are excellent for multi-day courses, as there are classrooms, gun ranges, students can stay in the dorms, and eat meals onsite. We used a large classroom with plenty of table space, decent lighting, and a large 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.

In this course we cover the Remington 870, Mossberg 500/590, and Benelli M1-90/M2. Shotguns represented were about half Remington 870's, and the other half a mix of Mossberg 500's and 590's. There were two Benelli M1-90’s in the class.

We started with an introduction of all present. Everyone was supplied with a course manual, inspection forms, and supplier lists of where to obtain parts, tools and accessories. We supplied every student with their own set of basic tools that are necessary to do most of the general work on the shotguns (short of specialty tools for shell latches and restaking detents, etc). Everyone was introduced and supplied with Slip2000 "EWL" Extreme Weapons Lubricant and #725 Cleaner Degreaser.

We showed our procedure of a series of checks that we use to make sure everything is working correctly, and why we use this series of checks. Everyone was taught a hands on session of the eight basic functioning cycles of the shotguns. From there we broke the same eight functioning cycles down further in greater detail.

We went through the proper way to remove barrels from each type of shotgun. With the barrels removed, they were inspected, in this class I think every barrel was heavily fouled. The fouling inside the barrel is generally plastic from the shot wadding, mixed with powder and shot residue. Everyone was shown that they needed to clean the chamber and bore, as these are different diameters and require different brushes. They were also shown all the other hidden areas of the barrel that need to be kept clean for proper functioning of the bolt assembly and barrel to receiver fit for lock up etc. Also shown were a multitude of tools, brushes, and jags for cleaning the barrel. Everyone with fouled barrels were allowed to clean them, as a hands on session of trying the different methods and tools shows what works better. Everyone was supplied with Slip2000 #725 Cleaner/Degreaser, and Carbon Killer/Cutter, which help to cut through the fouling rather quickly. After a short session of barrel cleaning, the fouling was removed.

Barrels were inspected for damage, stress, missing parts etc. We also showed the differences between old and new styles of Remington 870 retaining cap designs, and showed why these shouldn't be intermixed.

Note: One student’s Remington 870 had a barrel had no magazine cap retaining detent. It turned out that this shotgun was an Express model that normally doesn’t come with a detent, but had a Remington factory magazine extension tube mounted on it which requires the retaining detent to secure it. We supplied the student a detent, spring, and tools to install the detent, which now the barrel has a detent.

Next we showed how to remove the bolt assemblies from each of the different weapon systems. Everyone learned that the Mossberg system is more involved when compared to the Remington and Benelli systems. The group consensus was that bolt removal and installation is not for every Officer on the Mossberg system, as we showed examples of damaged parts where people tried to force things back together when they weren’t properly aligned.

We then moved into the bolt assemblies, slides, action bar assemblies, and how they integrate together. Bolts were disassembled and reassembled, and inspections were done, showing where debris and corrosion is found, and why we recommend that certain things be inspected and cleaned on a regular basis. Students were introduced to splined pins, and shown the proper way to remove and install them. The 870's were inspected for old versus new parts, the difference in era's of 870 parts, and shown a hands on difference of forged vs MIM (metal injection molded) parts and why we recommend using the forged parts on police 870's. The 500/590 bolts were disassmbled, and people were shown the changes in eras of these parts, and that there is a difference in the right & left extractor assemblies and why.

Magazine tubes and their internals were gone through. When we allow people to clean the magazine tubes using a magazine tube brush, it’s always amazing to see how much crud comes out, and IMHO the magazine tube should be scrubbed clean of debris on a regular basis. Magazine springs were covered, and there were a few students that had sporting shotgun springs, of which were replaced with heavier springs. Students were also shown why we recommend tactical magazine tube followers over the stock cup shaped ones. No magazine tubes were found to be bent or damaged.

After lunch we moved into forend assembles, stocks receivers and trigger groups. Forend assemblies were taken apart using the proper wrenches, then the forends were inspected, action bars inspected, and things were reassembled and indexed correctly. It was shown how the action bars have a timing that controls the shell latches, and if the action bars are damaged or bent that the timing could be off. Two forends at the class were not indexed correctly, and once repaired they cycled just fine. Butt stocks were removed and inspected. Several butt stock assemblies didn't have lock washers, which were replaced upon reassembly. Every wood stock was inspected for cracks, and all made sure they had stock bearing plates and were shown their importance. We went through stock repair on wood and synthetic stocks, to include alterations. Receivers were inspected where stocks mount to, and replacement and repair was covered.

Note: One Officers Remington 870 was having feeding issues, where the rounds would occasionally hang up inside the magazine tube and not release when the action was cycled to the rear. He cleaned a lot of debris out of the magazine tube. The magazine tube spring was found to be in okay, shape, but I gave him an Wolff spring that has more tension. Upon inspection of his action bar / forend assembly, his Surefire forend was loose. Whoever installed the Surefire forend hadn’t tightened the spanner nut enough, which caused the forend to be loose, and would cant to the side and twist the shell latches, which is mostly likely what was causing the feeding malfunction. We supplied him with end wrench, and he indexed and tightened things down, and now his shotgun is feeding correctly.

Day-2 started with a review of everything that we covered the previous day. We then moved into trigger groups, starting with the Remington 870, then the Mossberg, and ending with the Benelli. Everyone was shown how the entire trigger groups work, what can be disassembled and what cannot due to availability of parts, inspections, maintenance, mechanical safeties, changes in designs, Police/Military models vs sporting models, and how the carrier integrates during cycling. We also showed common mistakes that people make with trigger groups, the problems in function, and how to correct any issues. After trigger groups were put back together, we showed how the carriers integrate, how the slides with action bars work, and how/why the lock forward cycle works.

Shell Latches on the Remington system was next. We covered proper staking and why, how they get damaged or misaligned, and their replacement. We demonstrated, and then allowed people to use several different staking tools that we brought. The ejection systems were gone through, showing how the Remington system gets damaged, how to replace & make repairs, and lastly tuning.

Note: Two Officers had ejection assembly issues on the Remington 870’s. The first Officers 870 was one that had been taken out of service as it wouldn’t eject. Upon close inspection it had a broken ejector spring. He was supplied with a new ejector spring & rivet, along with the tools, and he teamed up with others to do a proper replacement, so now it works.

The second Officers 870 was taken out of service due to the barrel rotating in the receiver. Upon inspection, it was found that the front tip of the ejector track was broken off and missing, this is something we see when barrels are forced back into the receiver when they are not properly aligned. We supplied him a new ejector track, spring and rivets, and tools. He teamed up with others and removed the damaged ejector parts, then installed the new ones. Now things work properly.

Then end of the day was a review, followed by all shotguns being reassembled, then inspected and gauged to make sure everything was in spec and ready to go back into service.

Here is a brief overview of what is covered:
Headspace and wear inspections
Action and function
Barrel inspections
Fore-end assembly & action bars
Bolt assembly (extraction & spring, firing pin, retractor spring, flexitab cuts)
Ejector inspection, repair & replacement
Slide assembly inspection
Stem adjustments
Hook Space
Magazine spring, retainer & followers
Shell latches, inspections, adjustment & replacement
Custom accessories & enhancements

Greg Sullivan "Sully"
SLR15 Rifles
(763) 712-0123