With the SAAMI and CIP standardization of the .300 Whisper caliber as the .300 AAC Blackout, the distribution of this cartridge has greatly increased. More and more users appreciate the extremely flexible caliber also, but not only, because of the fully functional subsonic loads in semi-automatic weapons. You can't talk shop about the .300 AAC Blackout – its correct name according to CIP – without starting with the .300 Whisper. The .300 Whisper was developed in the early 1990s by the head of innovative firearms and ammunition manufacturer SSK Industries, J.D. Jones, along with a host of other Whisper calibers (6mm to .510). Jones' basic goal was to create new calibers, all of which were optimized for use with subsonic loads through smaller case volumes and heavy bullets. For the .300 Whisper, Jones necked up the 35.56 mm .221 Remington Fireball case to .308" (7.82mm) bullet diameter.
This also earned it the nicknames .300 Fireball or .300-221, but much more important was the fact that the cartridge, on the one hand, fit into the magazines of the proven AR15 platforms and, on the other hand, enabled flawless cycling with subsonic and supersonic loadings without additional conversion or parts switching. This was probably the most important foundation stone for a great commercial success. What stood in the way, as rumored behind closed doors, were the rather hefty license fees that Jones demanded from any commercial manufacturer of his caliber. This and the fact that the .300 Whisper was never officially standardized by SAAMI led to the silencer manufacturer Advanced Armament Corporation (AAC), part of the Remington Outdoor Group, making minimal changes to the cartridge and having it officially listed with SAAMI in order to make it commercially usable for itself, but also for other gun and ammunition manufacturers, license-free. After Staff Sergeant Daniel Horner (now a member of the U.S. SIG Sauer IPSC/Action Team) won the U.S. Multigun Nationals with the .300 BLK in 2011, the caliber spread like wildfire. The cartridge is very flexible in terms of usable bullet weights and the spectrum ranges from 110 to 230 grains.
Hornady .300 Blackout in Germany?
The term "blackout" does not refer to the hopefully never-occurring emergency of a complete, prolonged power blackout, but to the relatively new .300 BLK caliber that has already been introduced to German law enforcement and military forces. At the end of October 2022, for example, the news made the rounds that the Schleswig-Holstein Ministry of the Interior had signed a four-year framework agreement with Heckler & Koch worth a total of around 1.68 million euros.
In the first year of the contract, 60 HK437 training weapons and 140 operational weapons are to be delivered. In subsequent years, the renowned Black Forest-based supplier will have to deliver 200 operational weapons including accessories. For the state police, the HK437 including silencer replaces the 9mm MP5, which has been in service for over 50 years. This makes the state of Schleswig-Holstein the first major customer to put this member of the new HK weapons platform into service. The HK437 is based on the HK433 in 5.56x45 and features minor detail modifications such as a slightly modified multi-cartridge rotating head bolt, a gas block positioned further to the rear and an independent, optimized .300 BLK magazine.
Two new loads of Hornady's TAP line of LE ammunition with MonoFlex and Frangible bullets.
The new Hornady .300 Blackout TAP SBR 111-grain MonoFlex bullet from the law enforcement "Tactical Application Police" (TAP) series is designed specifically for short barrel rifles (SBR) from 6.75" (171 mm) to 11.5" (292 mm). The cartridge complies with FBI protocol (standardized target ballistics tests on various media) and is said to have a signature (muzzle flash and bang) reduced to the minimum without and with silencer.
An ideal lead-free training ammunition might be the .300 Blackout TAP with 110-grain heavy NTX bullet. Featuring a fully disintegrating frangible projectile with a copper alloy bullet core, AMP jacket for high accuracy and polymer tip, the cartridge can be used in indoor shooting ranges as well as on steel target media, even at short ranges, with reduced rebound and ricochet risk. A heavy metal-free primer in the primer pocket of the high-quality brass case successfully rounds off the .300 Blackout 110 Grains NTX TAP.