The Diamondback Firearms Obsidian Series DB15 is a 5.56 NATO semi-automatic rifle configured for versatile range, training, and field use. It features a 16-inch 4150 CrMoV barrel with a 1:8 right-hand twist, mid-length direct-impingement gas system, and a Diamondback Obsidian muzzle brake mounted on 1/2x28 threads. The flattop forged aluminum upper receiver and 15-inch M-LOK handguard provide a practical foundation for accessories and an aftermarket optic. A Magpul CTR stock, MOE K2 grip, and 30-round PMAG complete the user-focused configuration.

Key features

• 5.56 NATO chambering supports widely available ammunition
• 16-inch nitride-finished 4150 CrMoV barrel with a 1:8 right-hand twist
• Mid-length direct-impingement gas system provides a balanced operating configuration
• Flattop upper receiver is optic ready for a user-selected sighting system
• 15-inch M-LOK handguard includes full Picatinny rail and QD mounting points
• Adjustable Magpul CTR stock accommodates varying shooting positions and gear

The Obsidian Series DB15 combines a practical AR-15 pattern layout with modern accessory mounting and dependable 5.56 NATO performance.