M16 Bolt Carrier Group - Billet Extractor, 5.56, SP4™

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SP4™ Extreme Wear Coating Technology is here! Outerwild Manufacturing produces thousands of M16 BCGs which are trusted by seasoned shooters and depended on by experienced builders. Our goal is to go above and beyond Mil-Spec expectations! Outerwild’s secret sauce: WE PRECISION GRIND. We machine and grind our BCGs to perform for tens of thousands of rounds. We grind the outside dimensions, and ALL three interior dimensions. The Extreme Wear Coating technology, SP4™ is applied to the bolt carrier, bolt, firing pin, gas key, cam pin, extractor, and gas rings. This thin film has the thickness of three (3) microns and a hardness of 3,000 on the Vickers scale. SP4™ advanced surface engineering capability reduces friction, improves wear resistance, increases reliability and is corrosion resistant while extending the life cycle of critical components.

Our BCGs with SP4™ Extreme Wear Coating are Polished to a Mirror-Like Finish and are #1 in Hardness, #1 in Flexibility and Elasticity and #1 in Low Coefficient of Friction (.01)

  • M16 Style Chrome-lined Carrier
    • Machined from 8620 Steel
    • Properly Heat Treated to 60 HRC
    • Final Grind Before Plating
    • SP4™ Extreme Wear Coating
    • Full-Auto Carrier is Backward Compatible with All Semi-Auto Rifles
  • 5.56/.223 Bolt
    • Machined from 9310 Steel
    • Heat Treated
    • Shot Peened
    • MPI Tested (Magnetic Particle Inspection)
    • SP4™ Extreme Wear Coating
  • Billet Chrome-lined Gas Key
    • Machined from Solid Billet of 4130 Steel
    • Properly Seated with Grade 8 Fasteners
    • Properly Staked
    • SP4™ Extreme Wear Coating
  •  Cam Pin
    • Machined from 4140 Steel
    • Heat Treat
    • SP4™ Extreme Wear Coating
  •  Billet Extractor
    • Machined from Solid Billet of 4140 Steel
    • Heat Treated
    • Shot Peened
    • SP4™ Extreme Wear Coating
    • Extractor Insert Included
    • Viton O-Ring Included
  • Firing Pin
    • Machined from 8640 Steel
    • SP4™ Extreme Wear Coating
  • 100% American Made
  • 5
    BCG SP4 Coating

    Posted by Robert on Jan 22nd 2024

    This BCG has got to be one of the best out there. The SP4 coating makes it feel slicker than glass and even better after adding your preferred lubricant. The difference is night and day when you pull that charging handle back. The chrome lining is very well done and the staking is excellent. I have about a 1,000 rounds through my rifle with this bcg and have had zero hiccups. No flaking of the coating and no discoloration. It is worth noting that the color of the bcg is actually a gloss black not a silver or chrome as it looks in the picture. Overall couldn’t be happier with it and will use for all future rifles.

  • 5
    Looks and Feels Great!

    Posted by Larry Propst on Nov 18th 2022

    Looking forward to testing it out!