Machined to USGI (United States Government Issue) specifications, the SIONICS M16 style Carrier includes a properly sized Mil-Spec Gas Key that is NP3 Coated and Heat Treated. The Gas Key is secured to the Carrier via OCKS (Optimized Carrier Key Screws) and properly staked, which mitigates the premature backing out of said fasteners. Each carrier includes a hand-installed gasket formed by aviation Permatex to the mating surfaces between the gas key and the carrier. By hand installing these Permatex gaskets, we significantly decrease the risk of under gassing.
SIONICS Bolts are manufactured from Carpenter 158® Steel. Each Bolt is HP/MPI (High Pressure / Magnetic Particle) tested and inspected. These Shot Peened Bolts, come equipped with a Sprinco Heavy Duty Extractor Spring and Black Spring Insert. In addition to the Carrier, the Bolt and Cam Pin have also been NP3 treated to enhance Corrosion Resistance and Carbon build-up.
Prior to shipping, all SIONICS Bolt Carrier Groups are Test Fired for function. Because of the Test Firing Procedure, the Bolt Carrier Group could show handling marks consistent with these Quality Control Procedures.
Due to the inherent nature of NP3 Coating, Tooling Marks may be present on SIONICS NP3 Coated Bolt Carrier Groups. Tooling marks are COSMETIC and have ZERO effect on function. Being that the NP3 Coating impregnates into the host material, it is much thinner and much less forgiving in hiding Tooling Marks. Other popular coatings such as Phosphate and Nitride are thicker and darker in appearance, allowing for Tooling Marks to be easily concealed. Regardless of Tooling Marks present on SIONICS NP3 Bolt Carrier Groups, every SIONICS Bolt Carrier Group is backed by our Lifetime Warranty that covers any Manufacturer Defect that would affect function.