Primary Weapons Systems UXR: a convertible, modular and multi-caliber rifle

Primary Weapons: thanks to the patented "XChange" caliber exchange system, the PWS UXR can be configured for a wide range of applications.

Founded in 2008, the company was previously known primarily for its AR-15 rifles with long-stroke piston gas-operated system based on the AK-47 design. UXR stands for "User Exchange Rifle" and is therefore the model name for a modular, multi-caliber self-loading rifle that can be quickly converted by the user without tools. The UXR also works with a long-stroke piston gas-operated system and the centerpiece of the design is the patented "XChange" system.

Primary Weapons: to change the caliber, the bolt head, magazine well and barrel of the PWS UXR are exchanged (and the appropriate magazines are used). The magazine well is designed for cartridges of different lengths.

Only three parts are exchanged for a caliber conversion: bolt head, magazine well and barrel. A key element of the modified gas-operated rifle is the so-called "Bore Evacuator", which makes it possible to avoid readjusting the gas system every time the caliber and/or barrel is changed. The Bore Evacuator, which sits between the muzzle and the gas block on the barrel, is inspired by the "fume extractor" of modern cannons and reduces the back pressure, making the UXR even more suitable for suppressed operation. The interchangeable magazine well is designed for calibers with cartridge lengths of 71.12 mm (.308 Winchester, 6.5 Creedmoor, 8.6 Blackout) in the "Large Magwell" configuration and for cartridge lengths of 57.40 mm (5.56x45 mm NATO, .223 Remington, .300 Blackout, 6.5 Grendel, 6 mm ARC) in the "STANAG Magwell" configuration. There is also an additional "AK Magwell" magazine well for 7.62x39 and 5.45x39.

PWS UXR: ambidextrous operation for both left and right-handers

The PWS UXR is designed for maximum left- and right-handed ease of use, so that the buttstock can be folded down to either side of the weapon; the charging handle, which does not move when firing, as well as the safety/fire selector and the magazine release can also be operated from both sides. According to the manufacturer, the UXR will initially be available in 5.56x45/.223 Rem. and .300 BLK, with .308 Win. and 8.6 BLK soon to follow. According to the U.S. manufacturer, the range of calibers will then be expanded step by step.

The PWS UXR impresses with technical details such as the "Bore Evacuator" (concealed under the handguard) and is consistently designed for ambidextrous operation.

ACR – predecessor and successor to the Primary Arms System UXR

As is well known, the PWS UXR is not the first more or less successful attempt to establish a semi-automatic multi-caliber self-loading rifle or fully automatic multi-caliber assault rifle: just think of predecessors such as the Magpul Masada, Bushmaster ACR, Remington ACR, Robinson Armament XCR from the USA, or the MCIWS or AAR from India, to name but a few.

It therefore remains to be seen whether the new UXR from Primary Weapons Systems, with its many innovative design details, will prevail and prove itself in the future. At first glance, it seems to have what it takes.

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