Dark mode is

Product Unavailable

Unfortunately, the following product is currently unavailable through Rainier Arms.

Fathom Arms Enhanced BCG


*Includes FATHOM 3D patch for a limited time*

Carrier Material: Case Hardened 8620 Steel

Finish: Black Nitride. This advanced low friction coating minimizes the need for lubricants.

Radiused Gas Key: 4130 Steel, attached with Grade 8 hardware, torqued to correct specifications, and then properly staked into a milled “valley” using a press stake to properly deform the metal. This procedure ensure proper positioning and gas key locking.

Ejection Port: Area is milled with added material for more strength and rigidity

Cam Pin: Hardened 4340 cam pin

Firing Pin: Mil Spec firing pin made of 8740 steel, center-less ground and Hard Chrome coated

Carrier fits AR15/M4 compatible style Rifles (i.e.) .223/5.56mm, .300BLK, 6.8SPC

Laser Engraved Fathom Arms “FATHOM” logo

Bolt Assembly: The Bolt Assembly is machined from solid round stock to TRUE Mil-Spec dimensions. The entire external surface, including the bolt bearing surfaces, is CNC ground after heat treatment to ensure proper and unaltered tolerances.

Material: Case Hardened 9310 Steel, Shot Peened

Finish: Black Nitride coated

Extractor: 4340 Steel, Magnesium Phosphate coated, Mil-Spec Extractor Spring, O-Ring, and Black Extractor Spring Rubber Insert, Shot Peened

MPI: Magnetic Particle Inspected

HPT: High Pressure Test

Bolts are lot tested under MIL-STD-1816 for both HPT and MPI

Proudly made in the USA

More Information
Google Customer Reviews Google Customer Reviews