TexasCHLforum.com

silverbear wrote:http://www.thefirearmblog.com/blog/2010 ... 0-aac-blk/

Introducing the Advanced Armament Corp. 300 AAC BLACKOUT (300BLK). This system was developed to launch 30 caliber projectiles from the AR platform without a reduction in magazine capacity and compatible with the standard bolt.

Full power 123 grain ammunition matches the ballistics of the 7.62x39mm AK, has 37% more energy than 5.56mm M855, and 9% more than 6.8 SPC TAP 110. In fact, from a 9 inch barrel, the 300BLK has more muzzle energy than 5.56mm M855 from a 16 inch barrel. When 300 BLK is used in a 16 inch barrel, it has 23% more energy than 5.56mm M855 from a 16 inch barrel - with much higher-mass projectiles for a more dramatic effect on the target. Or choose subsonic cartridges for optimal use with a sound suppressor - 220 grain Sierra OTM (open-tip match) bullets vastly outperforms a 9mm MP5-SD in penetration and long range accuracy.

Due to the high efficiency of the cartridge, less powder is used than 5.56mm, which results in a rifle that is a comfortable to shoot - even with a short barrel.

Reloading dies available from Forster products, Reamers and headspace guages available from Pacific Tool and Gauge.

DESIGN OBJECTIVES
• Create a reliable compact 30-cal solution for the AR platform
• Utilize existing inventory magazines while retaining their full capacity
• Create the optimal platform for sound and flash suppressed fire
• Create compatible supersonic ammo that matches 7.62x39 ballistics
• Provide the ability to penetrate barriers with high-mass projectiles
• Provide all capabilities in a lightweight, durable, low recoiling package

REASONS 7.62x39 WAS NOT CONSIDERED
Extreme cartridge taper
• Reduces reliability of feeding in AR Magazines
• Reduces Magazine capacity
• Cartridge taper induces considerably higher bolt thrust-
exacerbating the AR Bolt's weaknesses
• Requires a larger Bolt Face which reduces Bolt Locking Lug strength-
exacerbating the AR Bolt's weaknesses
Limited projectile selection
• 0.311" diameter not a common option in most modern bullets