AR-15 Ammo Continually Evolving
More often than not, in the world of new cartridges, someone who has a fanciful idea to reach a new ballistic plateau comes up with a cartridge, and then gunmakers respond in kind with firearms adapted or designed around the new round. Quite often, the evolution is parallel.
The .500 Smith & Wesson and the X-frame revolver are good examples; the pair was conceived and born together. But the AR-15, more than any other rifle in history, has broken that mold and reversed the development path of norm. In the last decade especially, a plethora of new cartridges have appeared that were designed just for the AR-15.
Quite a lot of the rounds came from military ballisticians and ammunition companies trying to improve on the 5.56X45mm NATO’s battlefield lethality—or lack thereof. Long-range shooters and competitors also sought to improve on the much-maligned 5.56, those marksmen seeking a projectile fired from that particular rifle that had enough gas to stay supersonic longer and slip the wind better.
Hunters, too, are using the AR-15 to tackle any and all of North America’s small and big game, and still another set of developmental talent wanted to give shooters the option to tackle big game or stop a vehicle or boat in its tracks via big-bore hunting and interdiction rounds. It seems the only limit for engineers, ballisticians, wildcatters, hunters, and shooters has ben making a new round fit in the rifle’s magazine—and it is amazing what will fit in an AR magazine.
One of the reasons the AR-15 has proven so popular with shooters and spawned this new crop of purpose-built cartridges is the gun’s inherent ability to easily adapt to just about any military or police, hunting, shooting, or competition mission. With a steady trickle of improvements since the rifle’s adoption by the U.S. military in the early 1960s, the AR-15 has evolved into a rifle that is extremely reliable, accurate and, most importantly, adaptable. The rifle’s relatively simple design also made it a natural platform for experimentation.