SIG Sauer MCX vs. MCX Virtus

The Latin word “virtus” means “virtue,” and the firearm of the same name from the house of SIG Sauer is a powerful tool in skillful hands. First presented on the world market in 2013 and then revamped in the summer of 2017, the MCX assault/self-loading rifle has an extremely modular design based on the AR with an indirect gas impingement system with short-stroke gas piston and rotating bolt.

SIG Sauer MCX Virtus semi-automatic rifles with different barrel lengths
The MCX Virtus is available with barrel lengths of 9” (228 mm), 11.5” (292 mm) and 16” (406 mm). Soon, a German, semi-automatic civilian version with a 16.6” (422 mm) barrel will be available for sports shooters.

In comparison with a standard AR-15 employing a direct gas impingement system (DGI) implemented by the original inventor, Eugene Stoner, the MCX/MCX Virtus features a Short Stroke Piston System with adjustable two-position gas block unit.

An additional, notable difference are the dual recoil springs above the bolt carrier in the receiver instead of the buffer tube (typical of the AR) in the frame.

This construction makes it possible for the MCX/MCX Virtus to be equipped with a foldable stock.

Last but not least, this modular semi-automatic firearm promises a simple caliber and barrel switch between .223 Remington (5.56×45) and .300 Blackout (7.62×35) as well as different barrel lengths and configurations.

SIG Sauer MCX vs. MCX Virtus: what are the differences?

In contrast with the MCX, the MCX Virtus has a “SIG Matchlite Duo” two-stage trigger  with clean characteristics and a trigger pull of approximately 2,040 to 2,720 grams instead of a military hard standard trigger.

The cold hammer forged barrels in lengths of 9” (228 mm), 11.5” (292 mm) and 16” (406 mm) with 1–7” twist also show a stronger contour. The free floating handguard of the MCX Virtus is designed in the current M-LOK instead of KeyMod configuration.

The locking lugs of the MCX Virtus are conically designed to ensure cleaner cycling and increased service life.

Additionally, the stock (foldable to the left) with five locking positions has been improved, thus reducing the firearm’s length from 90.2 cm to 67.3 cm, and also allowing the firearm to be adjusted and leaving it ready to fire even in folded-in position.

Eight different handguard variations are available in standard and suppressed configuration. 

In combination with all stock, barrel and finish variations that means that the SIG Sauer MCX Virtus ultimately comes in over 500 configurations to be selected from!

SIG Sauer MCX assault rifle disassembled into main components 
When stripped, you can recognize the main components of its forerunner model, the MCX: the dual recoil springs on the bolt carrier.
SIG Sauer MCX Virtus
SIG Sauer MCX Virtus.

We tested the new MCX Virtus model live in the USA

Assault rifle SIG Sauer MCX Virtus in action on the shooting range
At the SIG Sauer Academy, the SIG Sauer MCX Virtus – here equipped with the Romeo4 reflex sight – was completely convincing when test-fired in demanding and dynamic drills.

We were able to thoroughly test the MCX Virtus during our visit to SIG Sauer Academy at the end of April 2018.

Our test firearm in .223 Remington caliber was set up with a Romeo4 reflex sight and performed absolutely convincingly in practice.

This model will be available in a civilian version in Germany in the near future. Exactly when is still an open question, but we expect that it will be available in fall of 2018 in specialist shops in Europe and we will inform you accordingly.


For further information about SIG Sauer USA firearms, please visit the manufacturer's website. 

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