SIG Sauer MCX Virtus 5.56 AR-15 Upper Receiver Conversion - Black - 11.5"

Manufactured by Sig Sauer
Manufactured by Sig Sauer
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Note: This barreled upper receiver assembly has a barrel length under 16” and is therefore subject to all NFA rules and regulations. Know your local laws before purchasing.

Convert your standard AR-15 lower receiver into the SIG Sauer MCX Virtus in 5.56 NATO with this complete upper receiver assembly. This MCX Conversion Kit features an 11.5” barrel with an adjustable gas piston system and a tapered bolt lug design that smooths out the cycling and improves bolt life. The barrel is threaded 5/8x24 but includes a 3-prong flash hider. The free float aluminum handguard features M-LOK attachment slots and has an opening for easy access to the gas setting. Included with this MCX Virtus Upper Receiver is a lower receiver adapter and X-Fold stock adapter for attaching standard buffer tubes and stocks. Because of the internal recoil mechanism, this setup can be fired with the stock folded. This 5.56 upper receiver assembly comes with the SIG Matchlite Duo Trigger which features a smooth and consistent two-stage trigger pull with a crisp break. The SIG MCX Virtus Upper Receiver Conversion Kit is a quick and efficient way to completely upgrade your rifle.

Note: It is recommended to use the included trigger. Use of a standard AR-15 trigger may cause malfunctions.

  • Chambered in 5.56 NATO
  • 11.5” cold hammer forged barrel
  • 3-Prong flash hider
  • Short stroke gas piston with internal recoil system
  • Tapered bolt lug
  • X-Fold stock adapter
  • Lower receiver adapter
  • 90° muzzle adapter for non SIG suppressors
  • Two-stage Matchlite Duo trigger
  • Picatinny QD socket

Sig Sauer is a world-renowned firearms manufacturer with a rich history of innovation and design leadership. No other firearms manufacturer is so highly regarded and so universally respected for the quality, reliability, and safety of its products. Since 1864 they have expanded their product line to include suppressors, optics, ammo, and airguns to provide customers with a greater range of firearms and equipment.
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Barrel Length11.5
BrandSig Sauer
Caliber Gauge5.56 NATO
Gas System LengthCarbine
Gas System TypeShort Stroke Gas Piston
Muzzle Device3-Prong Flash Hider

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