The Story

What is a WP870?

The 12-Gauge shotgun is perhaps the longest-serving firearm in American law enforcement history and continues to be the most prevalent long gun in the armories of police agencies across the country. While most law enforcement shotguns are typical and unexciting, there are specific versions that hold a unique appeal. One of those is the "Witness Protection 870", or 'WP870'.

This is the original "Shockwave" type shotgun and was used by the U.S. Marshal Service beginning in the mid 1980s. These firearms were designed for the Witness Protection Program to be carried under cover of a jacket or trench coat and readily available against a close threat. They utilized the Remington 870 platform and the shortened barrel lengths ranged from 12.5 inches to 14.5 inches. The original stock was reshaped to what's called a birdshead very similar to today's Shockwave grip.

The U.S. Marshals Service never called it the Witness Protection shotgun. Instead, they called it the Marshal’s Service Short Shotgun. A Marshal named Lynn Jordall came up with the idea and worked with an armorer at Glynco named Gene Thompson to produce the first of these shorty shotguns. According to Thompson, he built the first prototypes, and when they decided to produce the shotgun en-masse, they contracted the creation of the bird’s head grips out to Jim Wilson of Wilson Combat. Wilson was young at the time, and he hadn’t formed his premiere firearms company just yet.

The 'WP870' gains its nickname from its adoption and use by the United States Marshals Service. Fellow gun scribe Chris McLoughlin outlined the beginnings of the original guns in a 1984 article. According to McLoughlin, Gene Thompson, Lynn Jordall and Jim Wilson built three prototypes. This was a collaborative effort with each man working on a select feature to produce the most effective platform. The result was a cut-down Remington 870 with a 14.5-inch barrel, a custom-built hand stop and, most significantly, an ergonomic grip that retained the shape of the original factory stock. Other modifications included a slotted shell lifter to assist in clearing a short-stroke-induced double feed and a unique sling system.

The early versions utilized barrels trimmed to 14.5 inches and the cylinder bores modified to accept Mossberg pattern chokes. Around 240 of these guns were created and fielded for various roles in the Marshal’s Service, including Witness Protection. The U.S. Marshals Service created these specialized shotguns for close-range protection roles within the Witness Protection Program. They were designed for high firepower in tight spaces.

Jim Wilson was a talented machinist whose modest shop was located on Oriole Street in Brunswick, Georgia. Wilson saw the potential for other government, law enforcement and civilian sales of the WP870. Wilson provided two distinct services regarding the WP870. The first was a conversion of an agency shotgun. The second was to convert a customer’s personal 870 into a WP870. In 1984, the conversion cost was listed as $214.80. Because this was a conversion of a non-NFA shotgun, the BATFE classified it a short-barreled shotgun (SBS), which mandated a $200 tax stamp for individuals. Later, Wilson became a Remington manufacturer and received receivers and parts to build 50 guns. Since these were manufactured in the WP870 configuration, the BATFE classified these guns as Any Other Weapons, or AOWs, making them subject to a $5 AOW tax stamp. Unfortunately, the arrangement between Wilson and Remington did not continue, and no more WP870s were manufactured as AOWs.

As with any combat shotgun, the shotgun was given a shorter pump to allow access to the loading port while the slide is in the rearward position. One of the marshals’ requirements of the Witness Protection 870 was that it be concealable under a jacket. The original designers came up with an ingenious solution to carry the 25-inch shotgun. The hand stop, which was installed at the end of the magazine tube to prevent the user’s hand from slipping in front of the muzzle, also served as a sling receptacle. A traditional sling swivel was installed at the rear of the pistol grip. The key to this system was the design of the sling. The designers utilized an M1 Carbine sling with a quick-release snap that was mounted to the hand stop. The shotgun could be slung under a jacket in an upside-down configuration. To present the shotgun, the user would grasp the pump with his or her support hand, reach across their body and unsnap the sling. This freed the shotgun, and the support hand pulled the gun from under the jacket for a reasonably efficient presentation.

Why build one?

Ente always liked using the Remington 870 in Call of Duty Black Ops II and had the idea to build a shotgun visually similar to the ‘Sawed-Off’ from Counter-Strike. Recently Remington released the Model 870 Tac-14 Hardwood which is homage to the WP870. Since the release, unfortunately they seem to always be out of stock after 2 bankruptcies and buyout of the firearms manufacturing arm of the original Remington now RemArms.

Ente being the type of person to build what he wants, decided to get the parts together to build a short 870. Ente already had an 870 Receiver with a four shell magazine tube and he had an idea of a short 14-inch barreled shotgun with wood pump & hand grip and started looking around. He wanted to add a +1 shell extension to get magazine tube approximately the same length as the barrel and to have to ability to mount a sling.

How did he do it?

Ente found Wilson Combat and picked up the +1 extension to increase the 870 to a 5+1 shell capability. After he started searching for wood furniture, specifically the wood ‘birdheads’ grip. After searching for that he found pictures of the Tac—14 Hardwood and the listing on Remington’s website. Ente thought it was neat that the exact concept he was trying achieve was already a commercial product. After doing some more looking around for furniture Ente knew he wanted a ‘Corn Cob’ style pump, the old police style. He found a NOS [New Old Stock] Walnut Pump and ordered a wooden handgrip to match. After seeing the Tac-14 Ente did some more research and came across the story and use behind the WP870. This only made Ente want to build one even more since there is historical significance to the gun as well. When it came to the barrel Ente found that an 18.5 inch barrel is the most common and he was planning on purchasing one to cut down to 14 inches. He found someone selling a 14-inch barrel for an 870 that was blued and had a bead sight already installed. This saved him a bit of work and refinishing.

Ente found SladeStreetTactical while looking for parts and really liked their heat shields. They had a Tac-14 specific heat shield but it is polymer and Ente wanted a metal shield so it can gain finish wear and patina with time. He found the 6-Hole 870 Metal heatshield in their shop and reached out to them to verify measurements. Chris responded and let me know it is 14 inches overall and there is a 1-inch tab that can be trimmed off to fit the 14-inch barrel properly. Ente found the rest of the parts on MidwestGunworks, which includes the bolt, bolt slide, fire control group, takedown pins, pump forend and nut.

Since the Receiver had a 4 shell tube and Ente wanted to install an extension there was some work to be done. In the magazine tube there are 2 dimples that prevent loading more than 4 shells which need to be flattened out or filed off to allow the shell to pass through. There is a tool made specifically for this, which Ente used with some oil and a few taps with his punch hammer to drive the dimples out of the magazine tube. He put the tube on the anvil of his vise and peened the dimples to keep them flat and allows the detent swage to be released easily. Ente opted not to file or drill the dimples because he didn’t want holes in the magazine tube.

After getting that sorted out he installed the Walnut Pump on the forend, Ente then installed the birdheads grip onto the receiver, installed the bolt, bolt slide and got those aligned with the pump arms. He got the fire control group in place and installed the takedown pins. Then he got the barrel installed in the receiver and married it all together with the +1 Tube Extension, spring and follower.

Ente trimmed the heat shield down and chamfered the edge to prevent cuts and snags. He polished the entire thing inside and out with red scotch-brite and wiped it down with 99% Isopropyl Alcohol. Ente then painted it with a flat black high temp ceramic coating and baked it on in multiple stages. He then added some finish wear to get it started and coated it with some semigloss clear coat to give it a similar finish to the bluing on the barrel. He installed the heat shield with the included hardware and some semi permanent Loctite.

Ater it was assembled Ente did a functions check at the workbench, went to the range and ran a box of birdshot through it to break it in.

Ente built his WP870 for about $700 USD with new & used parts.

(Tools not included in that price.)

Receiver‍ ‍Remington $150

Bolt ‍Remington $125

Bolt Slide ‍Remington $20

Fire Control Group ‍‍Remington $100

Takedown Pins ‍‍Remington $15

Pump Forend ‍‍Remington $40

Pump Forend Nut ‍‍Remington $10

Barrel‍ ‍‍Remington $100

Tube Extension ‍ Wilson Combat $55

Heat Sheild SladeStreetTactical $75

Furniture Remington $120(Free - Gifted)

Total: $700

Accessories

Ente got an M1 Seatbelt Sling in Black to be able to carry the shotgun and coincidentally it matches the orignal WP870 sling.

Sling‍ ‍USGI M1 Sling‍ ‍$20

After a few months of research, careful planning, sourcing parts and tools, the build was finished.

A list of parts and tools used can be found below. For those who want to build their own WP870.

Thank you for reading if you made it this far!

-Ente & Maltz

Founders of Functional Reserve Militia