Engineering & Technical Division

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A lot of people will disagree with me, but I like Sage EBR Tactical Stock Systemfor the M1 Garand. It is a drop-in stock that does not require permanent modifications to the rifle.




From thefirearmblog


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The X7 is billed as extremely accurate, durable and low maintenance. To test this, the first thing I did was degrease it with brake cleaner.



Upon examining this rifle, one realizes a lot of effort went into ergonomics. The VLTOR stock has Quick Detach (QD) swivel mounts on both sides, the receiver end plate has one and there's one on each side of the hand guard. The hand guard is milled from two pieces of 7075T6 aluminum so well fitted they look like a monobloc. The handguard and rails run forward to the gas block, with side mounted rail sections as well. Next Gen is making those removable for future models.

Mechanically, it has a crisp Geissele trigger that breaks consistently at 5 lbs, a Noveske stainless polygonal barrel, mid-length gas system, BCM bolt carrier group (properly staked) and Gunfighter charging handle, a billet lower with forged upper, a proper impact extruded 4 position buffer tube, also staked, and a very advanced ceramic coating all over. This provides a low friction surface that most gas particulates simply can't adhere to. The magazine well is flared and cut so even Magpul PMags and Thermolds will drop free easily. The rails are perfectly to spec so no force is needed to slide accessories on. The muzzle brake is loud and blows a lot of gas at bystanders, but recoil is reduced to negligible levels. The charging handle can be slightly stiff for smaller shooters, due to the heavy recoil spring. Sights are optional but available, since most shooters prefer to choose their own.

From a 16" carbine, sub 2" 10 shot groups were easily attainable at 100 yards using a scope, good commercial ammo and a sandbag. Best group so far was 5/8" (300 feet ASL, 53 degrees F, 55% relative humidity, using Federal Premium 62 gr ammunition.)



The X7 is not cheap, but it's a fair price for the combination of accuracy, durability and ergonomics. It's on par with other high end ARs, and pushes the envelope on materials and capabilities. So far, I am convinced this is a rifle one can trust one's life to. It is a pleasure to shoot, amazingly accurate, and tough as a keg of nails.

By Michael Z. Williamson. Photos by NGA




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As part of our service to our valued customers, one of the things that we are really proud of is our service to customers.



Shown here are some photos of an M60 being serviced by one of our master technicians.







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5.7x28mm cartridge on a M4 equals 50 +1 firepower for intense CQB duties!


The AR57 is a replacement upper receiver that allows a standard M4 to be converted to 5.7×28mm and use a FNH USA-style 50-round mag. The empty cases are ejected through the mag well.


Initially researching AR57’s M4 conversion, I had to go to their website to see what everyone was talking about—because somehow this product has been flying under my radar for some time. I was aware of FNH’s 5.7×28mm cartridge, the modernistic P90 PDW and the Five-seveN pistol. After perusing AR57’s website, the concept of a 5.7×28mm upper on an M4 really intrigued me. I contacted the company and spoke to Markus Laukers, who began educating me on what I had been missing.

First came the cartridge. FNH USA developed the 5.7×28mm as a new CQB cartridge that could effectively penetrate body armor without over-penetrating soft and hard targets. The cartridge was introduced in the P90 platform, followed by the Five-seveN pistol. The first loading of the 5.7×28mm was known as the SS190. When fired from the P90 PDW, the SS190’s 31-grain projectile had a reported velocity of around 2,300 feet per second (fps). Due to the armor penetrating capabilities of this round, distribution was limited to military and law enforcement agencies.



The 50-round mag must be inserted into the front rail and then seated above the chamber, limiting the space for optics and other accessories.


The AR57 conversion is a complete upper that will fit on any standard M16/M4 lower receiver. The one-piece upper is machined from aircraft-grade aluminum and features integral Picatinny rails at the 9, 3, and 6 o-clock positions. Two raised rails, one forward and one at the rear of the receiver, allow the use of fixed sights or optics —depending on the user’s needs. The action is a straight blowback with no locking lugs on the bolt. A non-reciprocating charging handle is located on the right side of the receiver to chamber a round or clear the weapon. Due to the pressure and bolt travel of the AR57, a shorter recoil spring buffer is needed to ensure reliability. The non-tapered barrel is 16.04 inches in length and is equipped with a flash hider that is threaded in a 1/2×28 pitch. This allows the AR57 to accept most screw-on suppressors and muzzle brakes.

At the heart of the AR57 is the FNH-style magazine. FNH USA shook the firearms industry when they introduced a feeding system where the magazine is mounted parallel to the barrel and rounds sit at a 90-degree angle to the barrel. The base of the magazine consists of a round feeding platform and contains a spiral feeding system that aligns the round with the chamber. While it sounds complicated, it is actually very simple and has proven reliable.

By Rob Garrett


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