Putting several hundred rounds through a Gemtech Integra upper in 300 BLK. Sounds like a dream assignment, and it was.

Athlon Outdoors recently hosted its first-ever Rendezvous at the beautiful Gateway Canyon Resort in Gateway, Colo. It was there where I got to put the Gemtech Integra 300 BLK through its paces. As one person expressed, “other people’s guns and other people’s bullets — it doesn’t get any better!”

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The Integra 300 BLK is a direct result of a government solicitation for a “Suppressed Upper Receiver Group” (SURG).

The SURG concept is to have an integrally suppressed upper receiver group that is designed for continuous suppressed use. Part of the solicitation included a reduction in gas blowback, as well as limits on the heat signature. While I’ve previously evaluated the Integra in 5.56mm, I hadn’t had any time with the 300 BLK version.

The Scoop on the Gemtech Integra 300 BLK

As with the 5.56mm version, the Integra 300 BLK has several unique features that contribute to its design. An 11-inch, 1:8 twist, barrel provides the basic foundation for the Integra 300 BLK. A shroud for the G-CORE baffle permanently attaches to the barrel, making the overall length 16.1 inches. That makes the Integra 300 BLK a one-tax stamp rifle.

In addition, the barrel features a unique bore evacuator that is in front of the gas block. This acts as an expansion chamber and bleeds gas prior to the gas block. The bore evacuator also serves to reduce the back pressure and blowback in the shooter’s face.

Gemtech worked with NEMO Arms to design a patented, pistol-length gas block that works in conjunction with the bore evacuator to eliminate much of the blowback. In order to reduce gas leakage and heat, the gas tube on the Integra uppers press fits into both the gas block and the receiver. The final design all but eliminates any leakage and ensures enhanced reliability.

The heart of the Integra is a G-Core monolithic baffle, which is machined from 6AL4V Titanium. It has a number of recurving chambers that slow and cool the gases. Each chamber is optimized for the temperature and pressure and the first chambers are opened up to decrease pitting and erosion.

All it takes to remove the G-Core is a socket wrench that fits the square bore opening. The edges of the G-Core are designed to scrape the carbon buildup inside the tube during removal.

The entire system is mounted to a NEMO Arms billet 7075-T6, upper with a Seekins Precision rail system.

Hitting the Range

On the range, the Integra 300 BLK proved to the be the quietest thing on the line. Indeed, everything else sounded very obnoxious when compared to 220 grain subsonic loads shot through the Integra 300 BLK.

We first ran the Integra 300 BLK on an HK 416 select-fire lower receiver. I had the job of doing several full-auto magazine dumps for the videographer. The Integra 300 BLK was both quiet and reliable.

I also engaged several steel plates out past 50 yards. Throughout our range time, I noticed not only the reduced sound signature, but also the lack of blow back. According to Alexander Crown, Gemtech’s Director of Marketing, the average sound signature of the Integra 300 BLK, when using 220 gr. subsonic loads, is around 128 dB.

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I hope to complete a full evaluation of the Integra 300 BLK in the near future. I also look forward to seeing the results of Smith & Wesson’s recent purchase of Gemtech. By combining Gemtech’s technology with “Big Blue’s” manufacturing capability and market presence, Gemtech will quickly climb to the top of the suppressor market.

MSRP on the 300 BLK Gemtech Integra Upper is $1,999.

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