The history of the 300 Blackout sometimes seems confusing, so it would make sense to take a trip into the past and get the detail on this interesting cartridge. Judging also by the sheer number of headstamps and variations available, it remains a fascinating cartridge to collect and to try and chase all the various new ones continually popping up.
It may be bold, but a case could be made that at least some of the credit for the 300 BLK should probably go those fine folks at Remington. It was during 1963 that they launched the .221 Remington Fireball, trying to create a very accurate target pistol based on their Model 600 action. That resulted in the XP-100 bolt action pistol, one of the first handguns for competitive target shooting. When the XP-100 was discontinued, Thompson Center took over and this was (sort of) where the story starts. As with many new cartridge developments, it did not take too long for the wildcatters to take notice and start to neck the 221 Fireball up and down.
One of the legends in the firearms industry who had a life-long interest in the Contenders as well as handgun hunting and who did immensely important work in the field of subsonic ballistics is JD Jones from SSK Industries.
He might not have been the first to neck the 221 Fireball case to .30cal, but his 1992 design ended up in being registered as the 300 Whisper, the first in a line of Whisper designs. According to The American Rifleman, he can almost be seen as the father of modern subsonic ballistics. The 300 Whisper was not as successful as was hoped for, for 2 main reasons: Firstly the lack of affordable factory loaded ammunition, and secondly and probably more importantly the 1994 Assault Weapons Ban. With the expiry of the ban in 2004 the AR-15 became an extremely popular rifle. The AR-15 can almost be regarded as the “Barbie doll for gun owners” – there are just no limits to dress up your AR-15. Fast forward a few years, and the concept of a subsonic assault/modern sporting rifle again became important. That was when Robert Silvers, Director of the R&D department of Advanced Armament Corp. (AAC), was contacted by a government customer to design/rediscover that idea. The 300 Whisper was a registered trademark and therefore could not be used as Remington only used SAAMI-approved ammunition and the 300 Whisper was CIP-registered. The idea also was to have a cartridge that is not limited to just subsonic loads, but to provide the most optimum .30cal performance from a standard AR-15 platform, all that is needed is just a barrel change. The name Blackout was chosen to distinguish it from not just the Whisper, but from the various .30cal “Fireball” variations of the same cartridge with different chamber dimensions. Today the 300 Blackout is probably the second most offering on the AR-15 platform after the 223 Remington.
The AAC 83 headstamp in 5.56×45 and 7.62×51 was a made by Igman of Yugoslavia for Nordac Manufacturing Corp. (NMC) in Fredericksburg, Virginia, and the initials stand for “American Armaments Corporation”. This was a deceiving contract intended for El Salvador. ADI is by Australian Defence Industry. AMMO INC is by Ammo Incorporated, Scottsdale, AZ. AP is by Armscor of the Philippines. APEX was by Discreet Ballistics, Plainfield, NH, cases made by Jagemann for them. ATL ARMS was by Atlanta Arms, Covington, GA. Cases in all probability made for them by Starline. The 2 CG dated headstamps from 2018 and 2019 were Carl Gustaf, loaded by Nammo in Sweden.
Gemtech is situated in Boise, ID. The GORILLA brand is owned by PCP TACTICAL, LLC, Vero Beach, FL. The nickeled case was their Gorilla Silverback line and was only available for a short period. The B on the primer is the marking used by CCI to identify their #BR4 small rifle primer, or “Ultra-premium primer for Small Rifle Bench Rest competition.” HPR is by High Precision Range, Payson, AZ. HSM is by Hunting Shack Ammunition, Stevensville, MT. JAG is by Jagemann Technologies, Manitowoc, WI. JBA is by Jamison International, Sturgis, SD
MAI is by Modern Arms International of Phoenix, AZ. MAST is by Mast Technology Inc., Blue Springs, MO, and used on military and custom ammunition. During 2020 the company was acquired by Ultra Defense Corp. (UDC). The m/m is by Karl-Heinz Müller Munitionshandel and the case was manufactured by Süddeutsche Hülsenmanufaktur. Nexus is from Nexus Ammunition, Phoenix, AZ, a division of Strategic Armory Corps. NOVESKE is a line of rifle ammunition made by Nosler. NOVX is by Timberghost Tactical, LLC, Calhoun, GA. It is a one of their brands with SST’s NAS3 cases. OATH was by Oath Ammunition, Rockledge, FL. PNW was by Pacific North West Arms, Potlach, ID. Company has been out of business since 2016. PRIME is by Prime Ammunition, Las Vegas, NV. . ProGrade was by ProGrade Ammunition, Stevensville, MT, with cases made for them by Starline. They are no longer in business. PWS is by Primary Weapons System, Boise, ID.
The S&B with light blue p/annulus is the subsonic loading. SCO was by Silencerco, West Valley City, UT and had the cases made for them by Aguila in Mexico. SSA is by Silver State Armory, Pahrump, NV, now owned by Nosler. SUMMIT was by Summit Ammunition, Attalla, AL but they are no longer in business.
TNQ is by “Team Never Quits” from Snake River Shooting Products, Emmett, ID. UNDRWD is by Underwood Ammo, Charleston, WV. X-Treme is by X-Treme Bullets, Lewiston, ID
Snap-cap by Vector Shooting Supplies China
