7.62 Precision Custom Firearm Finishes

Instructions for the installation of The Mako Group’s tactical shotgun furniture kits on Mossberg 500 series shotguns. These instructions are also applicable to installation on Maverick 88s.

Before starting installation, remove existing forend and buttstock by following the instructions here: Mossberg 500 Disassembly.

Before begining the installation of any aftermarket forend on a Mossberg 500 series shotgun, it is necessary to determine which style of forend your shotgun has. Mossberg has shipped shotguns with three types of forends. The first type has a long slide tube, and aftermarket forends are built for this style of slide tube. The second type is assembled on a short slide tube (6.75″). Forends will need to be modified and installed with an adapter nut to fit the 6.75″ slide tube. The third style has no slide tube. The rails are molded permanently into a one-piece forend. If you shotgun has this type of forend, you will need to purchase a long (7 5/8″) slide tube to replace it with.

Modifying the PR-MO Forend to fit a short (6 3/4″) action slide tube

To modify the aftermarket forend to fit the shorter slide tube, you will need a 1 1/4″ hole saw, an extended adapter nut, and a drill or drill press. This modification will simply extend the larger inner diameter at the front of the forend to accept the longer adapter nut

Run the hole saw into the front of the forend deep enough to allow the rim of the extended nut to contact the forend. The lenght of this cut is not too critical, as long as the nut can be inserted fully into the forend.

Clean up the cut and the forend will be ready for installation.

Forend Installation

Slide Forend onto action slide tube

Insert forend nut into the front of the forend and thread onto action slide tube. Tighten nut. Install forend and slide tube assembly onto the shotgun by following assembly instructions here: Mossberg 500 Assembly.

Buttstock and Pistol Grip Kit Installation

Slide Stock Adapter onto rear of reciever

Insert and tighten rear screw to attach Stock Adapter to receiver.

Thread the Receiver Extension fully into the back of the Stock Adapter

Align groove in bottom of reciever extension with set screw and tighten set screw firmly against receiver extension. Do not overtighten. 

Place pistol grip in position on stock adapter and start pistol grip screw. To install the pictured folding AGF-43S, fold the grip first and then insert screw. For standard AG-43 grips, open the bottom door of the grip and insert scew through bottom of grip. For any other AR-15 pistol grip, follow manufacturer’s instructions. Tighten Screw.

Start Buttstock onto receiver extension. Pull OUT on butstock adjustment latch and slide buttstock onto receiver extension. To adjust length of pull, squeeze latch and pull buttstock backward or push forward to desired position.

Mossberg 500 in OD and Black with The Mako Group's Tactical Shotgun Upgrade Kit