Mossberg

Mossberg Kits

Mossberg kits are bundled upgrade packages that convert Mossberg 500, 590, 590A1, Maverick 88, 930, and Shockwave shotguns from factory configuration to tactical, hunting, or home defense setups. Mossberg kits include FLEX conversion kits from O.F. Mossberg & Sons, tactical stock adapter kits from Mesa Tactical, premium walnut furniture kits from WOOX, rail kits from Black Aces Tactical, and pistol grip kits in 12-gauge, 20-gauge, and .410 bore configurations. Each kit contains the stock or forend components, mounting hardware, and fasteners needed for installation without permanent modification to the receiver. TactaBlue stocks Mossberg kits alongside dedicated Mossberg 500 stocks and forends for individual component upgrades across the Mossberg 500 series platform.

Mossberg FLEX Conversion Kits

FLEX System Overview

The Mossberg FLEX System is a tool-free modular platform that allows Mossberg 500 and Maverick 88 owners to swap stocks, forends, and recoil pads without tools in under 60 seconds. Mossberg introduced the FLEX System in 2012 with 16 interchangeable accessory components, including 9 stock options, 4 forend options, and 3 recoil pad thicknesses. The FLEX Tool-Less Locking System (TLS) stock adapter uses a rotating latch mechanism that locks the stock to the receiver and releases with a quarter-turn of the locking device. FLEX conversion kits add the TLS adapter system to standard Mossberg 500 and Maverick 88 shotguns that did not ship with FLEX compatibility from the factory.

FLEX Conversion Kit Options

Mossberg offers 5 FLEX conversion kits in 12-gauge and 20-gauge configurations.

• Stock and Forearm Adapters Kit, 12 Gauge (#96024, $101.00) — includes the FLEX TLS stock adapter and forend adapter for full FLEX compatibility with all FLEX stocks, forends, and recoil pads
• Stock and Forearm Adapters Kit, 20 Gauge (#96025, $98.00) — includes both TLS adapters sized for 20-gauge Mossberg 500 and Maverick 88 receivers
• Stock Adapter with Pistol Grip Kit, 12 Gauge (#96026, $90.00) — includes the FLEX TLS stock adapter and a FLEX pistol grip with sling swivel stud for converting to a Mossberg Cruiser-style home defense configuration
• Stock Adapter Kit, 12 Gauge (#96022, $67.00) — includes the FLEX TLS stock adapter only for adding FLEX stock and recoil pad compatibility
• Stock Adapter Kit, 20 Gauge (#96023, $65.80) — includes the FLEX TLS stock adapter only for 20-gauge receivers

FLEX Accessory Components

FLEX accessory stocks are available in 5 configurations with Length of Pull (LOP) options from 12.5 inches (317.5 mm) to 14.25 inches (361.9 mm). The FLEX Standard Stock is available at 12.5-inch, 13.5-inch, and 14.25-inch LOP in black, Mossy Oak Break-Up Infinity, and Mossy Oak Max-4 camouflage finishes ($87.00 to $105.00). The FLEX 4-Position Hunting Stock ($157.00 to $168.00) provides 4 LOP positions for adjusting fit across multiple shooters. The FLEX 6-Position Tactical Stock ($120.00) uses a telescoping buffer tube with 6 LOP positions for tactical and home defense applications. FLEX recoil pads snap onto FLEX stocks in 3 thicknesses: small at 0.75 inches (19.1 mm, $34.00), medium at 1.25 inches (31.8 mm, $34.00), and large at 1.5 inches (38.1 mm, $43.00). FLEX forends include the Standard Forend ($41.00 to $53.00) and the Railed Forend ($53.00) with integrated Picatinny tri-rail for mounting lights and lasers.

Mossberg Tactical Stock Adapter Kits

Mesa Tactical LEO Gen II Telescoping Stock Kit

The Mesa Tactical LEO Gen II Telescoping Stock Adapter and Conversion Kit converts the Mossberg 500 and 590 from a factory buttstock to an AR-style telescoping stock with pistol grip for adjustable Length of Pull (LOP) and improved recoil control. The Mesa Tactical LEO Gen II kit includes a 6061 aluminum stock adapter, AR-pattern buffer tube, telescoping stock, Mesatac Trego rubber overmold pistol grip, Quick-Detach (QD) sling swivel flush cup, wrenches, and all mounting hardware. The stock adapter bolts to the Mossberg receiver using the factory stock bolt torqued to 20 foot-pounds (ft-lb). The buffer tube threads into the adapter and accepts any mil-spec AR-15 stock.

Mesa Tactical LEO Hydraulic Recoil Stock Kit

The Mesa Tactical LEO Hydraulic Recoil Stock Kit (#90120) includes a KynSHOT RB5100 hydraulic recoil reducing buffer that replaces the standard AR-15 buffer and reduces felt recoil by up to 90%. The KynSHOT buffer provides 3 adjustable damping profiles — low, medium, and heavy — adjusted with a flat-blade screwdriver through a set screw on the buffer body. The hydraulic buffer is designed for pump-action shotguns, because the recoil damper does not interfere with the pump action cycling, unlike semi-automatic shotguns where a recoil buffer can affect the gas-operated action cycle.

Mossberg Furniture Kits

WOOX Gladiatore Furniture Kits

WOOX Gladiatore furniture kits replace the factory Mossberg 500, 590, 590A1, Maverick 88, and Shockwave stock and forend with handcrafted American Claro walnut components featuring M-LOK forend slots, QD sling mounts, and a Microcell recoil pad. WOOX produces 5 Gladiatore configurations for Mossberg shotguns.

• Gladiatore Stock + Forend Kit ($459.00) — full buttstock and M-LOK forend set in American walnut with raised cheek comb, ambidextrous design, and aggressive checkering
• Gladiatore Club Grip + Forend Kit ($329.00) — club-style grip and M-LOK forend for the Mossberg 500, 590, 590A1, Maverick 88, and Shockwave platforms
• Gladiatore Stock ($289.00) — buttstock only with adjustable LOP and recoil-reducing pad for the Mossberg 500, 590, and Maverick 88
• Gladiatore Forend ($169.00) — M-LOK walnut forend with checkered grip panels for the Mossberg 500, 590, and Shockwave
• Gladiatore Club Grip ($159.00) — ergonomic walnut club grip with aggressive checkering for the Mossberg Shockwave, 500, and 590

WOOX Gladiatore components are individually handcrafted from selected Claro Grade American walnut in limited production runs. The Gladiatore raised cheek comb provides consistent cheek weld height for use with iron sights, ghost ring sights, and red dot optics.

Mossberg Retrograde Walnut Stock and Forend Kit

The Mossberg Retrograde Walnut Stock and Forend Kit (#95377, $265.00) replaces the factory synthetic stock and forend with a classic walnut buttstock and corncob-style forend that matches the Mossberg 500 Retrograde factory configuration. The Retrograde kit uses American walnut with a satin finish and traditional checkering. The Retrograde walnut stock fits Mossberg 500, 590, and Maverick 88 12-gauge models.

Mossberg Pistol Grip Kits

Mossberg pistol grip kits convert the Mossberg 500, 590, 590A1, 535, 835, and Maverick 88 from a full buttstock configuration to a pistol-grip-only (PGO) configuration for compact storage and home defense. The Mossberg 12 Gauge Pistol Grip Kit (#95000, $45.00) includes a polymer pistol grip, stock bolt, flat washer, lock washer, rear sling stud, front sling stud, washer, and Allen wrench. Pistol grip kits are available in 3 gauges: 12-gauge (#95000, $45.00), 20-gauge (#95005, $45.00), and .410 bore (#95010, $45.00). A pistol-grip-only shotgun reduces the overall length by 8 to 10 inches (203.2 to 254.0 mm) compared to a full buttstock configuration. PGO shotguns increase felt recoil and reduce accuracy at distances past 15 yards (13.7 m), because the pistol grip provides no shoulder contact for recoil absorption or consistent sight alignment.

Mossberg Rail Kits

Black Aces Tactical Rail Kits

Black Aces Tactical produces 4 quad rail kits that replace the factory forend with an aluminum Picatinny quad rail for mounting lights, lasers, vertical grips, and accessories on all 4 sides of the forend.

• Mossberg 500/590/Maverick 88 Quad Rail Kit ($189.00) — full-length aluminum quad rail with 4 Picatinny rail sections
• Mossberg 500/590/Maverick 88 Slim Rail ($189.00) — narrow-profile aluminum rail for a slimmer grip diameter
• Mossberg 930 Quad Rail ($159.00) — aluminum quad rail for the Mossberg 930 semi-automatic action slide
• Shockwave Rail Kit ($234.00) — compact quad rail for the Mossberg 590 Shockwave 14-inch (355.6 mm) barrel configuration

Black Aces Tactical Side Shell Holder Kits ($15.00 to $45.00) mount to the receiver side and hold 4 to 6 spare shotshells for on-board reloading. The Mossberg Mag-tube Spike ($22.00) replaces the magazine tube cap with a serrated steel spike for breaching applications.

Mesa Tactical SureShell Carrier and Receiver Rail

The Mesa Tactical SureShell Carrier is a 6-shell aluminum side-mount shell carrier that attaches to the Mossberg receiver using the ejector screw and trigger assembly pin holes without disassembly of the receiver internals. The SureShell Carrier uses rubber friction tubes that secure each shotshell in the carrier. The Mesa Tactical receiver-mount Picatinny rail installs on the receiver top using the factory plug screw holes and accepts red dot optics, ghost ring sights, and magnified optics.

Mossberg Magazine Extension Kits

Mossberg magazine extension kits increase the tubular magazine capacity from the factory 5+1 or 7+1 configuration to 8+1 or 12+1 capacity for tactical and competition use. The Mossberg 930/940 Magazine Extension Kit (#104761, $59.99) extends the semi-automatic shotgun magazine tube to 12+1 capacity. Magazine extension kits include the extension tube, magazine spring, follower, and barrel clamp. The Mossberg 590 uses an open-end magazine tube design that accepts extension tubes without modification, while the Mossberg 500 uses a closed-end magazine tube that requires replacement of the magazine tube cap or the full magazine tube assembly for capacity increases.

Mossberg Shotgun Platform Compatibility

Mossberg kits are designed for 6 primary Mossberg shotgun platforms that share the Mossberg 500 receiver design.

• Mossberg 500 — the base pump-action platform in 12-gauge, 20-gauge, 28-gauge, and .410 bore, designed in 1961 with over 11 million units manufactured
• Maverick 88 — the budget variant of the Mossberg 500 with a cross-bolt safety instead of the 500's top-mounted tang safety. Maverick 88 shotguns accept most Mossberg 500 stocks, forends, and barrels
• Mossberg 590 — a tactical variant with an open-end magazine tube that accepts magazine extensions, available in 12-gauge and 20-gauge
• Mossberg 590A1 — the military-specification variant with a heavier barrel and aluminum trigger group that passed the United States (US) military qualification trial of 3,000 rounds of 12-gauge high-power buckshot without failure
• Mossberg 590 Shockwave — a 14-inch (355.6 mm) barrel pump-action with a Raptor bird's head grip, classified as a "firearm" rather than a shotgun under the National Firearms Act (NFA) due to its 26.37-inch (669.8 mm) overall length
• Mossberg 930 — a gas-operated semi-automatic shotgun that uses a different stock mounting system than the 500 series pump-action platforms

Verify kit compatibility with the specific Mossberg model before purchasing. The Mossberg 500, Maverick 88, 590, and 590A1 share the same stock mounting bolt pattern. The Mossberg 930 uses a different stock bolt and receiver interface and requires 930-specific stocks and forends. The Mossberg 590 Shockwave accepts 500/590 forends but uses a bird's head grip instead of a full buttstock.