Geissele Stress-Proof Bolt Assembly w/Extractor 05-2991

Geissele Stress‑Proof Bolt Assembly with Extractor 05‑2991 is a high-performance drop-in bolt assembly for AR‑15/M4 platforms, engineered for extreme reliability and longevity. Machined from forged Carpenter® 465 steel (often referred to as Carpenter 158+), each bolt undergoes shot-peening, high-pressure testing, magnetic particle inspection, and is finished with Geissele’s proprietary Nanoweapon® coating for outstanding corrosion and wear resistance. The included extractor is made from premium 300M stainless steel and also coated with Nanoweapon®, providing consistent function and enhanced durability.

• Material: Carpenter 465 or “158+” forged steel bolt; 300M stainless extractor
• Finish: Nanoweapon® coating on bolt and extractor for ultra-hard surface and low friction
• Compatibility: AR‑15 / M4 platforms chambered in .223 Rem, .223 Wylde, 5.56 NATO, and .300 Blackout
• Weight: Approximately 1.54 oz fully assembled
• Quality Control: Shot-peened, high-pressure tested, magnetic-particle inspected for maximum reliability
• Includes: Bolt, extractor, extractor spring, O-ring insert, ejector, ejector spring & pin