AAR SLR15 Law Enforcement Shotgun Armorer Course, Defiance MO

Greg "Sully" Sullivan

Too Established

When: January 25-26, 2023

Where: Defiance, Missouri

We conducted a 2-day (16-hour) Law Enforcement Shotgun Armorer Course that was hosted by the St. Charles County Sheriff's Dept. This was our first time teaching an Armorer's week at this location, and we look forward to future courses. The training offered plenty of table space, decent lighting, with a great HDTV and a large screen with projector and screen system that allowed us to show lots of animated graphics of the weapons system and powerpoint of detailed pics of gun parts, especially when looking at finer detail things like machining, stress cracks & wear.

This course covers the Remington 870, Remington 1100/1187, Mossberg 500/590, and Benelli M1-90/M2/M4 and Nova/Supernova type shotguns. Officers are welcome to bring other shotguns as well, we only request that if they need any possible replacement parts that they bring them with to the class if possible.

This class was all Law Enforcement Officers from Missouri, Kansas, Nebraska, and Oklahoma.

The shotguns present in this course were a mostly Remington 870's, one Remington 1187, a few Mossberg 500 / 590's, and an older Winchester 1200. Officers bring shotguns to work on, and we always recommend that Officers bring shotguns that are not working correctly or broken, as we look at this as a learning opportunity to figure out what is not working correctly, and Officers can make repairs onsite to get them back into working condition.

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. 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 cycles of function on the shotguns. From there we broke the same eight 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, Slip2000 Piston Parts & Choke Tube Cleaner, Slip2000 Carbon Killer, which help to cut through the different types of fouling. After a short session of barrel cleaning, the fouling was removed.

This class seemed to have a lot of heavily fouled barrels, as when we allowed people to clean there were a lot of barrels that people were getting lots of plastic fouling out. We supplied people with shotgun chamber brushes and rods, most weren't aware that shotgun chamber brushes existed. We also showed where shotgun ammunition may produce different types of fouling, from the plastic fouling, and black powder fouling as well. We supplied several different types of brushes, cleaning rods, solvents, jags,patches, etc, and people put them to good use.

Everyone got a hands on use of seeing how the different Slip2000 solvents work, especially 725 Cleaner/Degreaser, Carbon Killer and Choke Tube Cleaner. The Slip2000 Choke Tube Cleaner is great stuff, we use it on shotgun barrels, along with any gun barrels that get used for Simunitions, Force on Force, or UTM type ammunition where plastic fouling may occur. The Carbon Killer makes quick removal on black powder fouling.

Note: Several barrels were soaked in the Slip2000 Choke Tube Cleaner over lunch, which allowed the solvent time to loosen the plastic fouling, as a swab of a couple of patches and the fouling was gone.

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, and when I mentioned that barrels could come loose and fly off during shooting, of which several of those present had experienced this first hand and didn't know why.

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. Armorers 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.

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.

Day-2 started with a review of day-1. We went back through the magazine tubes. Specifically showing how the tubes are mounted to the receivers, and how to deal with damaged magazine tubes that get dented, bent or deformed.

We then moved into forend assembles, stocks receivers and trigger groups. Forend assemblies (action bar 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. We also showed variations and evolution changes in the forends.

Several of the shotguns present in this class had loose or misaligned forends. Loose and/or misaligned forends can cause things to go out of proper alignment, resulting in cycling issues. These cycling issues are generally feeding related where no shells or multiple shells were coming out of the magazine tube. Once everyone properly indexed and tightened the action bars and forend assemblies down, all of these shotguns worked properly. We recommend that Armorers have a good forend wrench, this way they can tighten or realign any forend that may need attention.

Note: One agency had several 870's with Surefire lights, which were found to have red thread locker on the forend / spanner nut threads (Action bar assembly). This was done by the agency's former armorer, as the forend spanner nut would continually come loose. This loosening of the spanner nut is something we see often when someone has added a new forend or tactical light, and not gotten the spanner nut tightened down enough. The cause of this is usually that the person who replaced it didn't have a proper forend spanner nut wrench, or often times some of the forends and taclites some with a flat piece of metal to use on the spanner nut, which is okay at best but doesn't allow the user to tighten the nut down enough for proper fit and holding powers. This is where we recommend that people obtain a quality forend end spanner nut wrench. It is also our recommendation that these threads not be thread locked, as they are very fine treads, which can lead to a thread locker being too much holding power and you cannot ever get the spanner nut off again, and heat cannot be applied to it easily due to heat effecting or melting the taclite.

We removed the buttstocks. Once removed, we showed the different bolts and washers that are used. Stocks were 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 repair and replacement was covered.

Note: The 1187 that was brought to class had been out of service due to it malfunctioning. When it was field stripped, it was found to be heavily fouled up, and dry. We had the Officer remove the recoil assembly, which was also found to be heavily fouled, and wasn't moving easily. Once the recoil assembly was cleaned and lubricated, and the internals of the gun and receiver were clean and lubricated, everything appeared to work just fine and nothing sticking anymore. The true test is it needs to be taken out to the range and test fired.

We then moved into trigger groups, starting with the Remington 870/1187, followed by the Mossberg, and Winchester. 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 870's is where we went next on the weapons system. We covered proper staking and why, how they get damaged or misaligned, and their replacement. We showed several different tools for aligning and staking shell latches.

The next thing we covered was the ejector systems. We showed the 4 piece system of the Remington 870, and how it gets broken, and how to make a replacement. We also covered the Mossberg ejectors, which is much less involved as compared to the 870 design.

Note: One of the 870's in class was found to have a loose ejector spring. We showed how to adjust this, and supervised while the Officer made the repair.

The 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
Trigger Systems
Stem adjustments
Hook Space
Magazine spring, retainer & followers
Shell latches, inspections, adjustment & replacement
Custom accessories & enhancements

Greg Sullivan "Sully"
SLR15 Rifles

(763) 712-0123