Glock OEM Glock 21 Threaded Barrel - 45 ACP, M16X1LH Thread Pitch - SKU: 39895 - UPC: 764503015564
Product Description
The Glock OEM Threaded Barrel for the Glock 21 (39895) is a factory-original replacement barrel engineered specifically for full-size .45 ACP Glock handguns, including the G21 Gen 4 and Gen 3 platforms. Manufactured directly by Glock in Austria, this factory threaded barrel guarantees drop-in fitment, exact chamber dimensions, and uncompromising cycling reliability when host firearms are outfitted with suppressors or muzzle devices.
Precision-hammer forged from high-strength ordnance steel and treated with Glock's proprietary surface hardening, this barrel features European-standard M16x1LH (Left-Hand) thread pitch geometry. Left-hand threads prevent suppressors and muzzle accessories from backing off under thermal expansion and heavy rapid-fire vibration schedules.
Included with the 39895 barrel is an original factory knurled thread protector to shield the delicate muzzle threads from impact damage and grit when operating without a muzzle device attached. Cold-hammer forging preserves precise rifling engagement for maximum projectile velocity and tight grouping downrange.
*Armorer Bench Notes & Real-World Staging Guidance:
Fitment Matrix: Fits Glock 21 (Gen 3 & Gen 4) .45 ACP pistols. (Thread pitch is M16x1LH; ensure suppressor piston or muzzle device matches this exact left-hand metric thread specification).
- Verify host Glock 21 is completely clear, magazine removed, and chamber visually and physically confirmed empty.
- Perform field stripping procedures to remove slide assembly, recoil spring, and factory non-threaded barrel.
- Clean slide interior and locking block surfaces of excess residue or grit.
- Insert the Glock OEM threaded barrel into the slide housing, ensuring the barrel hood seats fully against the breech face.
- Reassemble slide with recoil spring, mount onto receiver, perform function checks, and hand-tighten thread protector or suppressor piston counterclockwise (Left-Hand Thread).
Key Features
- Factory Glock OEM Manufacture: Original factory production ensures drop-in fit, proper unlocking timing, and factory safety lockup.
- M16x1LH Metric Thread Pitch: Left-hand metric threads resist loosening under heavy suppressor recoil and thermal expansion.
- Cold Hammer-Forged Steel Construction: Delivers high barrel life, uniform bore geometry, and exceptional accuracy retention.
- Included Factory Thread Protector: Protects exposed muzzle threads against drop impacts and surface abrasion when shooting unsuppressed.
- Hardened Surface Finish: Provides maximum corrosion resistance and wear protection inside duty holsters and high-friction slide contact points.
Product Specifications
- Brand: Glock
- MPN: 39895
- UPC: 764503015564
- Caliber: .45 ACP
- Platform Compatibility: Glock 21 / G21 SF (Gen 3 & Gen 4)
- Thread Pitch: M16x1LH (Left-Hand)
- Material: Cold Hammer-Forged Steel
- Finish/Color: Factory Black
- Includes: Threaded Barrel & Factory Thread Protector
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