Custom The APF Armory APF-4 is a rugged, semi-automatic tactical carbine chambered in 5.56 NATO. Built on mil-spec forged aluminum receivers, it is designed for law enforcement and professional applications, featuring an adjustable gas block for reliable suppression. [1, 2] Key Specifications: Caliber: 5.56x45mm NATO Action: Semi-Automatic Barrel Length: 11 in Upper & Lower Receivers: Mil-spec forged 7075-T6 aluminum with a hard-coat anodized finish Gas System: Mid-length with a pinned, adjustable gas block Barrel Profile: M4 contour, utilizing durable 4150 Chrome Moly Vanadium (CMV) Handguard: Extended M-LOK compatible handguard Ergonomics & Hardware: Safety: Ambidextrous safety selector Sights: Magpul MBUS flip-up sights for fast target acquisition Bolt Carrier Group (BCG): Mag-phosphate coated M16 BCG with a properly staked gas key