SLR15 Law Enforcement Shotgun Armorer Course, Ottumwa IA


When: February 12-13, 2020

Where: Ottumwa, Iowa

We conducted a 2-day (16-hour) Law Enforcement Shotgun Armorer Course that was hosted by Indian Hills Community College Law Enforcement Academy. This was our first time doing courses here, and we look forward to coming back for future courses. The onsite facilities offer plenty of table space, decent lighting, and a large screen and projection system that allowed us to project 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, Mossberg 500/590, and Benelli M1-90/M2 type shotguns. The training room offered plenty of table space, decent lighting, a media system that allowed us to show some powerpoint & detailed pics of the weapons systems and parts, especially when looking at finer detail things like machining, stress cracks & wear.

This class was a mix of Law Enforcement Officers from all over Iowa and Missouri

The shotguns present in this course were a mix of Remington 870's, Mossberg 590's, Benelli M1-90's & M2's. 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.

Note: Two Officers brought guns weren't working correctly. I like it when this happens, as this is what I call a learning opportunity. This allows us a hands on chance to figure out what is not correct, and fix it. In this case it was two Remington 870's that were jambing up when cycling, and a Benelli that wasn't feeding rounds correctly.

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, which help to cut through the fouling rather quickly. After a short session of barrel cleaning, the fouling was removed.

Note: Several barrels that were brought to class were having feeding/locking and extraction issues. Upon inspection it was found that these both had a heavy fouling build up inside the chamber. The Officers that brought these to class didn't know that there were chamber brushes for shotguns. We supplied them with chamber brushes and some Slip2000 Choke Tube Cleaner, and in a few minutes the fouling was removed, and we ran some action proving dummy rounds through them to confirm that everything was back in working order.

Note: Several barrels had heavy fouling inside that people couldn't seem to get clean with a traditional bristle bore brush or tornado brush. They took my advice and soaked the barrel in Slip2000 Choke Tube Cleaner. After letting it soak during the lunch break, they came back and ran a tornado brush through the barrel a few times and all the fouling came out. 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.

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.

Note: There was one Remington 870 that was missing the spring & detent which locks the barrel onto the magazine tube via that retaining cap, and another one that came loose and shot out when we inspected them. This allowed us to show how the system works. We supplied the Officer that was missing one with a new spring and detent, then gave them both a special detent staking punch for installation, and the got them corrected.

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. We showed how the bolts assemblies, slides, action bar assemblies, 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. 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. The 590 bolts were disassembled, 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, but we covered repair and replacement.

Note: One Officer brought a Benelli M4 to class that was having feeding issues. Upon removal of the internals of the magazine tube, it was found to be heavily gummed up with gooey lube/solvent, to the point that the follower was being hindered. He also found a broken magazine spring. He gave the magazine tube a good cleaning using a magazine tube brush and Slip2000 725 Cleaner/Degreaser solvent. We then gave him a Wolff XP magazine spring, and it worked better than before. We recommend the Wolff XP springs as a reliability upgrade, as you will notice the difference when ammunition is fed from the magazine tube.

Day-2 started with a review of day-1. 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 forends. Loose 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 shotgun that had an aftermarket polymer forend, was found to be loose. Being that it had been loose for quite some time, it had been cycled so much that damage to the polymer where it contacts the forend action bars had eroded away to the point that it could no longer be tightened down, and this was what was causing the occasional cycling/feeding when the action bars would get twisted.

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 replacement and repair was covered.

We then moved into trigger groups, starting with the Remington 870, followed by the Mossberg and 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.

The next thing we covered was the ejector systems. We showed the 4 piece system of the 870, 2 piece system of the Mossberg, and then the Benelli system. We covered how these are replaced, tuned, and proper inspections, showing several variations of tools and methods of how to perform repair & replacement.

Note: There were three Remington 870's in this class that had loose ejector springs. We walked these Officers through tightening and tuning these, and they are now back into proper working order.

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
Foreend 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