Special Operations Community Embraces 'Wildcat' Calibers.

• Author: Gourley, Scott R.

One phenomenon that has emerged from the U.S. special operations community over the last 10 to 12 years involves exploration and acquisition of small arms in new ballistic calibers.

Rather than the better known weapon designs in 5.56 mm, 7.62 mm, .50 caliber, and even the U.S. Army's emerging 6.8 mm Next Generation Squad Weapon, the community has embraced calibers like the .300 AAC (Advanced Armament Corporation) Blackout (.300 BLK), 6.5 Creedmoor, .300 PRC (Precision Rifle Cartridge), and both .300 and .338 Norma Magnum.

Often created as so-called "wildcat" rounds, prior to their broader acceptance and expanded production availability, these new caliber cartridges each provide a staggering array of design and performance specifics, experts said.

Recent requests for information released by U.S. Special Operations Command have identified specific command interest in a compact personal defense weapon chambered in .300 BLK.

"We're dealing in whole different types of mission sets," explained C.J. Dugan, vice president of business development at Maxim Defense, which has developed its own personal defense weapon designs. "The old way was, if you were doing 'low vis' close target reconnaissance or protection, you really only had an MP5 [9x19 mm Parabellum], which is hard to deal with these days because of parts. The only other answers you had were a pistol or a Mk18 [M4A1 (5.56x45 mm NATO) with a Close Quarters Battle Receiver variant with 10.3-inch barrel]. So trying to deal with a weapon system that would give you the right combination of distance and accuracy, and then trying to maneuver in a civilian vehicle with either only a pistol or 'a 10.3,' which you then had to keep out of sight, and then deal with and try to react to something, you kind of had limited expectations."

Crediting the early development work done by Advanced Armament Corp., Dugan offered a general description of the .300 BLK design, which included "taking a 5.56 [mm] case and necking it out to a .30 cal projectile, but utilizing pistol powder inside of that, which gives you a lot of muzzle velocities that you were losing in a short barrel with a rifle round.

"In my opinion, that was the genesis of why the 300 Blackout became popular in the SOF community," he said. "Because now, with the 300 Blackout--a .30 cal projectile loaded in a 5.56 case and burning pistol powder--you're now getting 2,000 feet per second out of a five-and-a-half-inch gun."

"Take a PDW for what it is--a...