The.300 BLK is based on the J.D. As for the rest of the weight? Part of that equation is the use of subsonic loads with heavy bullets and powder that burns completely in that abbreviated barrel. The 300 Blackout (pronounced “three-hundred black out”), officially known as the 300 AAC Blackout or the 300 BLK, or 7.62×35, is a rifle cartridge designed to be fired through AR-15 rifles with shorter-than-average barrels.

A 1:8 twist works best with the light-weight supersonic rounds. The two most important variables are the I want this to be the best ballistic trajectory calculator out there. lb Muzzle Velocity ft/sec. By keeping the M4/M16 in mind as the primary host during load development the designers could work up a host of cartridges that not only satisfied the ballistic requirements set forth, but also ensured mechanical reliability with the fewest changes to the weapon itself—with only a simple barrel change necessary for complete conversion.Robert Silvers, director of research and development for AAC said, "We started development in 2009, but most of the work was done in 2010. If you didn’t before, you can now easily see there are many factors to consider when selecting the best barrel length for your .300 BLK rifle and determine the effective range of the caliber. They are flatter shooting and, with less time in flight, less prone to the effects of wind. Much of the effectiveness of that round relies upon its 3,000 feet per second velocity, so when that drops by 500 feet per second or so, it’s not as effective.For testing, I used a CMMG Mk4 pistol. We make a Pistol/SBR load which is optimized for barrels between 7-11” and a Carbine load which is optimized for 16” barrels. As a reference, fired from the 16-inch barrel rifle, it developed a velocity of 1,915 feet per second.

The base stayed intact with only the tip of the bullet fragmenting along the way. Fireball as its parent cartridge.

Subsonic Handgun utilizes tried-and-true XTP® bullets that expand reliably at subsonic velocities. Where 300 Blackout really shines is in a suppressed AR-15. There were also efforts to introduce the AK-friendly 7.62×39 mm (also .30-caliber) to modern sporting rifles, but many of them ran into the cartridge’s case geometry challenge, where feeding can become a concern.

With supersonic rounds for maximum muzzle velocity to subsonic loads that quiet the roar by slowing the pace. Click to enlarge. The .300 AAC Blackout (designated as the 300 BLK by the SAAMI and 300 AAC Blackout by the C.I.P. Barrel twist rate matters as well, it’s another factor to consider when choosing barrel length and determining 300 Blackout effective range with your rifle.

Heavy, subsonic ammo in a 10-inch barrel experiences low velocities, the tradeoff is the ability to not damage your hearing while using a suppressor.

As one of the intents behind the development of this cartridge was to provide better terminal effectiveness when fired from short-barreled rifles, I decided to do some basic tests along those lines.Use of a short-barrel configuration instead of a full 16-inch rifle barrel will cause a drop in muzzle velocity up to several hundred feet per second. Home defense? As always, train with your rifle and make sure you know your intended purpose before you buy. In 2010 the team at Advanced Armament Corporation modified the cartridge slightly, adding.015 inch to the chamber throat length. Why are you using a firearm chambered in 300 BLK? The 16-inch barrel also delivers greater energy on impact regardless of the ammo type.

For all intents and purposes, there is very little difference in the ballistics of the .300 Blackout and 7.62×39 because the differences between them are so small with most loads. I will also give my opinion on the very simple question, “is it better than 5.56 NATO ?” Papers are written on that stuff.

Comparison of the .300 Blackout ammo used in this test. There’s no shortage of creativity among enthusiasts when it comes to the search for that “holy grail” of loads. They lack the mass to carry a proportionate level of energy at downrange, though.For an apples-to-apples comparison, the Hornady V-Max 110-grain load (also zeroed at 100 yards through 16 inches of barrel) has a muzzle velocity of 2,375 fps. 300 Blackout 190 gr Sub-X ® Subsonic Item #80877 | 20/Box Shhh... tell everyone! Part of today’s confusion over 300 Blackout effective range and barrel length often stems from this flavor.Suppressors minimize the chances of a sniper being located by sound, but they simply reduce audible emissions from their firearm’s muzzle end, not a projectile’s characteristic “crack.” To avoid it from giving a shooter’s position, subsonic .300 BLK loads use heavier bullets and adjusted powder charges—often tailored for a complete burn in a short barrel.The Hornady Sub-X 190-grain load, for example, exits the muzzle of a 16-inch barrel at 1,050 fps, where it is carrying 465 foot-pounds of energy. Hornady® Subsonic Ammunition — designed for accuracy and performance below the speed of sound — now comes in both rifle and handgun loads.