It’s been a bit more than 10 years since I pulled the trigger on a TNW Firearms Aero Survival Rifle (ASR) platform for the first time. I was impressed with the ingenuity and reliability of this uncommon caliber-convertible takedown system. Since then, the company has been steadily adding modifications, upgrades and additional caliber options to its catalog. Two of the latest features make for configuration options that are unique in the pistol-caliber carbine (PCC) marketplace: a patent-pending UB1 bolt and a new, 1911-based lower receiver.
The ASR is a blowback-operated, semi-automatic carbine that incorporates designs borrowed from both classic and modern guns with a few unique twists. All components are laser-cut, lathed or milled from high-quality billet materials. These guns are assembled with as few moving parts as possible for increased reliability.
The tubular upper receiver and the proprietary lower receiver are both machined from 6061-T6 aluminum and treated with a hard-coat anodized finish available in a variety of colors, including black (shown), grey, FDE and OD Green. The monolithic upper receiver sports an integral full-length Picatinny optics rail, and the fore-end portion is drilled and tapped at the 3-, 6- and 9-o’clock positions to support a provided 3.5-inch-long Picatinny accessory rail.
Left- and right-side ejection ports are present on the upper, as the bolt assembly can be adjusted to eject spent cartridge cases in either direction. The bolt-mounted, reciprocating charging handle is located on the right side of the receiver behind the ejection port. The bolt assembly does not lock open when the last shot has been fired. However, the bolt handle can be pulled back and tipped upward into a safety notch, MP5-style, to lock the bolt open.
The ASR’s slim, round-profile 16-inch barrel is made from 4140 chrome-moly steel and treated with a matte black, corrosion-resistant Parkerized finish. It is secured to the upper via a 3.32-inch ventilated-aluminum barrel nut. Giving the nut a few twists releases the barrel from the receiver for more compact storage, routine cleaning or caliber-conversion barrel swaps. All barrels now ship with threaded muzzles as a standard feature.
An AR-15 buffer-tube assembly caps off the rear of the upper receiver. Inside is a buffer and spring that support the heavy, 1-pound, 1-ounce steel bolt assembly. In this case, the buffer tube is of the six-position variety and was outfitted at the factory with an ATI adjustable stock.
The one-piece, aluminum lower receiver is secured to the upper using a pair of AR-inspired takedown pins. Pressing the pins out from left to right lets them drop free when removed. The external controls include a left-side, round-button magazine release, a cross-bolt safety button and a single-stage trigger. The lower is completed with a removable, mil-spec AR-15 pistol grip which, in this case, was a black polymer, finger-groove grip from Kriss USA.
TNW offers single-stage, match-grade trigger assemblies that can be installed at the factory or purchased separately. They shave about a pound off the trigger pull weight when compared with the standard version. This upgraded trigger was sent with the gun and broke with 3 pounds of pressure. It was also outfitted with a polymer trigger shoe.
Perhaps the key feature of the ASR system is the ease with which one of these PCCs can be converted to fire different calibers. Because the receivers and barrels are rated for standard-pressure and +P loads in 9 mm, .40 S&W and.45 ACP, these guns are strong enough to comfortably accommodate high-pressure rounds including .357 SIG, 10 mm and the potent .460 Rowland.
It used to be that a caliber-conversion kit for these guns included a cartridge-specific barrel, magazine and bolt. But, TNW has simplified caliber swaps with the development of its UB1, or Universal Bolt. Machined from 4140 steel, with the smaller parts made from S7 steel for added strength and durability, the UB1 is designed to automatically adjust to the size of the cartridge case being fired.
The bolt operates by pairing its spring-loaded, hooked extractor, located on the right side of the bolt, with what the company calls a cartridge guide. The guide, located on the left of the bolt, is also spring-supported, but it has a straight, no-hook profile. As a cartridge feeds from the magazine, the guide and the extractor exert pressure from either side of the bolt to center the cartridge base against the bolt face. When ejecting the spent round, the guide presses the empty case against the extractor to ensure proper control. The UB1 bolt is simple and reliable, and does not need to be traded out for caliber swaps. Instead, only the appropriate barrel and magazine are swapped. The entire procedure takes roughly 30 seconds, with no tools required.
Until recently, most ASRs were configured to feed from Glock-pattern, double-stack magazines. The model sent for the evaluation, however, was outfitted with one of the company’s new lowers sized for single-stack 1911 magazines. This configuration is a boon for those who prefer a slab-side semi-auto on their hip for defensive use. I’m a fan of 1911s chambered in 10 mm, so the formal performance testing for this ASR was conducted using a barrel in that caliber.
Most of the ASR’s weight is centered in the receiver set, which gives these PCCs a balanced and handy feel. As with most carbines in this class, the levels of felt recoil with 10 mm loads were on the modest side, making it a great fit for a variety of body sizes and skill levels. This is a flexible PCC with an ingenious design that makes it useful for many shooting roles. The threaded barrel, match-grade trigger and UB1 bolt contribute to an enjoyable shooting experience, and now, 1911 fans can put their preferred loads and magazines to work using this platform, making it a one-of-a-kind option in the marketplace. You can buy the 1911 model in one, three- or six-caliber conversion kits, so options abound for whatever you want.
