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KCI USA Glock 22 23 27 35 40 S&W 31 Round Extended Magazine Black KCI MZ012 UPC 851586008177
Product Description
The KCI USA® .40 S&W 31-Round Extended Magazine (SKU: KCI-MZ012 / UPC: 851586008177) is engineered to deliver sustained high-capacity firepower for full-size, compact, and subcompact .40-caliber Glock platforms. Designed specifically to support high-tempo tactical range drills, competitive shooting, and Glock-mag-compatible .40 S&W Pistol Caliber Carbines (PCCs), this extended magazine increases your onboard payload to 31 rounds without compromising structural feed geometry.
Constructed around a rigid, heat-treated hardened carbon steel skeleton insert, the magazine body prevents feed lip deformation, spreading, and elongation under continuous spring pressure. The internal steel chassis is encapsulated within a high-impact, abrasion-resistant polymer outer shell that resists drops, impact deformation, UV exposure, and harsh gun-cleaning solvents. Internal transit is powered by a high-tensile, heat-treated chrome silicon wire spring that maintains consistent upward tension against an anti-tilt, low-friction injection-molded polymer follower, guaranteeing positive round presentation from round 1 through 31.
Engineered to duplicate factory Glock magazine feed geometry, the KCI-MZ012 features ambidextrous magazine catch notches, ensuring seamless integration with standard right-hand or reversed left-hand mag releases on Gen 4 and Gen 5 frames. Numbered, rear-facing witness inspection ports allow shooters to verify round capacity at a glance during tactical reloads or competition staging. The standard polymer base plate is easily disassembled via dual side retention tabs for fast field cleaning and carbon maintenance after high-volume firing schedules.
*Armorer Bench Notes & Real-World Staging Guidance:*
Fitment Matrix: Compatible with Glock models 22, 23, 24, 27, and 35 (Generations 1, 2, 3, 4, and 5) and .40 S&W AR-40/PCC platforms utilizing Glock-pattern magazine wells. [CRITICAL NOTICE: Brand new high-capacity magazines feature extremely stiff chrome silicon springs engineered for sustained duty life. Loading the final 3 to 5 rounds by hand can be difficult during initial use; utilization of a mechanical speed loader (such as an UpLULA) is strongly recommended during the break-in cycle. Store fully loaded for 48 to 72 hours prior to primary range staging to allow the spring coils to take a natural set.]
- Ensure the host firearm is completely clear, magazine removed, and chamber visually and physically verified empty.
- Inspect the feed lips, follower orientation, and steel-reinforced feed track for any manufacturing debris or particulate before loading.
- Load .40 S&W cartridges sequentially into the double-stack column, using a magazine loader to seat the final rounds cleanly under the feed lips.
- Seat the loaded magazine firmly into the host firearm's magwell with the slide locked to the rear (or forward on closed bolt), verifying positive engagement with the magazine catch.
- Perform a manual feed check by cycling dummy/snap-cap rounds or conducting live-fire function verification downrange to validate bolt hold-open and follower lift.
Key Features
- 31-Round Extended Capacity: Maximizes onboard round counts for Glock .40 S&W handguns and AR-40 pistol caliber carbine platforms.
- Hardened Steel Skeleton Insert: Full-length internal carbon steel chassis preserves precise feed lip geometry and prevents body bulge.
- Impact-Resistant Polymer Shell: Rugged outer overmolding shrugs off hard ground drops, severe weather, and chemical exposure.
- Chrome Silicon Spring Drive: Heavy-duty spring maintains uniform lifting pressure across thousands of compression cycles.
- Rear-Facing Witness Holes: Numbered inspection ports provide immediate visual confirmation of loaded round count.
- Ambidextrous Mag Catch Reliefs: Fully functional across Generation 1 through Generation 5 reversible release configurations.
Product Specifications
- Brand: KCI USA®
- Model/Series: Glock Extended High-Capacity Magazine
- MPN / SKU: KCI-MZ012 / KCIMZ012
- UPC: 851586008177
- Caliber: .40 S&W
- Capacity: 31 Rounds
- Body Material: Steel-Lined Polymer
- Follower: Anti-Tilt Polymer (Black)
- Spring: Heat-Treated Chrome Silicon Wire
- Platform Compatibility: Glock 22, 23, 24, 27, 35 (Gen 1-5) & Glock-Pattern .40 S&W PCCs
- Country of Origin: South Korea
