BET ON BLACK – How I Learned To Stop Worrying And Love 300 Blackout

by Pete

As a follow up to last week’s Silencer Saturday where I professed my allegiance to the god that is 300 Blackout, I thought it might be a good idea to discuss my conversion in a little more detail. As I stated, my initial reaction came after comparing an MP5SD alongside a Sig Sauer Rattler with a proper decibel meter on loan from Allen Engineering. In the comparison, the Rattler shooting 220gr subsonic ammunition from Sig Sauer noticeably outperformed the MP5SD shooting 124gr JHP ammunition both in dB readings and old fashioned “that sounds loud” testing. Which is part of the reason I now love 300 Blackout.

Above: The Q Honey Badger in 300 Blackout

BET ON BLACK – How I Learned To Stop Worrying And Love 300 Blackout

Q Honey Badger and Trash Panda set up for Night Vision use.
Basic Background:

First, the basics. 300 Blackout is a rebirth of the 300 Whisper “Wildcat” round developed by J.D. Jones. In the late 2000’s the Naval Special Warfare Group (NSWG) requested the assistance of of Kevin Brittingham and his team – including Robert Silvers – at Advanced Armament Group (AAC).

At the time, the requirements were simple: develop a cartridge and bullets that could match or beat the ballistics of the 7.62×39 round being used against allied forces in the Global War On Terrorism (GWOT). In addition, the NSWG wanted to to use the AR platform with as many interchangeable parts as possible. Long story made short (behind the scenes details coming later) the 300 Blackout was born.

The Pros:

  • Plug and play – The same bolt, magazine and gas system as 5.56mm AR15
  • Heavy subsonic loads for suppressed shooting alongside fast subsonic loads for longer ranges
  • Reloading friendly

The Cons:

The cartridge gained SAAMI certification in January 2011.

Credit: SAAMI -

Since being accepted into the SAAMI Private Beach Club, cartridge and bullet development has resulted in an array of factory loadings for different use cases. I won’t stand up here and pretended to be a ballistics expert, but manufacturers are kicking out match grade target loads, varmint loads, defensive/medium game hunting rounds and more.

Which is part of the reason I decided to make 300 Blackout a staple round: as good as 9mm is for it’s intended use, even if the decibel readings were comparable, it would never be the short to intermediate range Swiss Army Knife that’s is 300BLK.

A Sample Of Ammo Choices:


  • AMMO TYPE: Rifle
  • CALIBER: 300 Blk
  • GRAIN WEIGHT: 220 gr
  • MUZZLE VELOCITY: 1000 fps
  • MUZZLE ENERGY: 488 ft-lb
  • MSRP: $25.95


  • AMMO TYPE: Rifle
  • CALIBER: 300 Blk
  • GRAIN WEIGHT: 125 gr
  • MUZZLE VELOCITY: 2200 fps
  • MUZZLE ENERGY: 1343 ft-lb
  • MSRP: $25.95

300 Blackout 190 gr Sub-X Subsonic!/

  • CARTRIDGE: 300 Blackout
  • BULLET: 190 gr Sub-X
  • PRODUCT LINE: Subsonic
  • APPLICATION Medium Game/Personal Defense

300 Blackout 125 gr HP American Gunner!/

  • CARTRIDGE: 300 Blackout
  • BULLET: 125 gr HP Match
  • PRODUCT LINE: American Gunner
  • APPLICATION: Varmint/Target/Match

300 AAC Blackout 190gr Subsonic Load – Target

The Discreet Ballistics 300 Blackout 190gr Subsonic Target Load is intended for use in semi-automatic and bolt action firearms chambered in 300 AAC Blackout. This round has been thoroughly tested to function in both pistol and carbine length gas systems. Discreet Ballistics gives its customers the option of choosing these loads for use in 16″ barrels or 7-11” barrels. ( Read more about why there are two loadings for different barrel lengths)

  • Brass: New Jagemann – 300BLK Sub – Factory Annealed
  • Bullet: 190 grain HPBT FMJ
  • Bullet Ballistic Coefficient: .530G1
  • Average Muzzle Velocity: 1050 FPS for 4150CMV barrels. Chrome-lined and stainless barrels may exhibit slower velocities (-50 to -100 FPS).

300 AAC Blackout 188gr Subsonic Load – Hunting / Self Defense

The Discreet Ballistics 300 AAC Blackout 188gr Selous Machined Expander is a subsonic hunting and/or self defense load that incorporates a machined copper 30 Cal projectile (the Selous bullet) which expands at subsonic velocities above 750 feet per second. This projectile was designed using state-of-the-art ballistics modeling software to maximize stability at subsonic velocities. Discreet Ballistics gives its customers the option of choosing these loads optimized for either 16″ barrels or 7-11” barrels. NEW: Customers can now choose between Lapua 300BLK brass or Jagemann 300BLK brass (Apex headstamp)

  • Brass: New Lapua 300BLK or New Jagemann 300BLK (Apex Headstamp)
  • Bullet: 188gr Selous Machined Expander – Solid copper projectile
  • Bullet Ballistic Coefficient: .404G1
  • Muzzle Velocity Range: 975-1050 FPS – 16″ AR; 875-975 FPS 7″ AR
The Guns:

We’ve talked briefly about development of the 300 Blackout round, subsonic (suppression) capabilities, and everything from target loads to defensive loads, but what about the guns? Sure, finding pistol caliber carbines is easy enough, and there are a lot of well made, fun and capable guns available – B&T, Angstad Arms, HK Clones and more. But finding a true rifle chamber in a pistol caliber, whether it is a semiautomatic or a bolt action, is a lesson in futility.

And rightly so: a look a Ballistics By The Inch shows near single-digit incremental velocity increases in pistol calibers in longer barrels.

Credit: Ballistics By The Inch - 9mm
Credit: Ballistics By The Inch - .45ACP

On the other hand, besides AR15 Style semiautomatic rifles (I have already professed my love to the Q Honey Badger and the Sig Rattler) chambered in 300 Blackout made by numerous manufactures, finding a bolt action rifle to push out 220grns of copper and lead is relatively easy. Which with a quality silencer and quality ammunition can make for a quiet, accurate and fun gun to own and shoot.

Ruger American – $529

CZ527 Suppressor Ready – $748

Remington Model Seven Threaded – $795

B&T bolt action rifle SPR300 cal. .300 Whisper / .300 Blackout – $5,000 (est)

The SPR300 is the perfect precision tool for all kinds of sniper assignments up to 150 meters. Due to its integrated suppressor the SPR300 is more silent than an air rifle. The SPR300 is designed as a quick take down rifle, enabling the operator to sneak into position, as it fits a small and inconspicuous carrying bag.

There are a wide variety of firearms chambered in 300 Blackout.

IWI Tavor X95

B&T semiautomatic rifle APC300 cal. .300 Whisper/.300 Blackout

Wrap Up – Love 300 Blackout

Is 300 Blackout the best caliber on the planet? Possibly, but it depends on your definition of “best”. I’d certainly call it the Swiss Army Knife of calibers: a wide variety of available platforms, part interchangeability (AR15), a good selection ammunition loadings and bullets, quality suppression capabilities, reloading friendly, enough force for defensive situations and medium sized game and broad acceptance by the firearms industry. I realize that most of you arrived at this conclusion years ago.

But for anyone asking, there will be no firesale on my personally owned pistol caliber carbines. They may not meet the levels of universal usability of the 300BLK cartridge, but they are still quiet and fun.

Thanks for reading.


Silencers - Science

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5 of 81 comments
  • Max G Max G on Jul 23, 2018

    Can someone please explain to my noob ass an apparently simple concept: how on gods earth is it possible to close the bolt on a 300BLK round in a 5.56 chamber where neither bullet nor the case neck should by rights be able to properly enter the barrel due to being whole 2mm larger than the barrel channel???

    • See 1 previous
    • Max G Max G on Jul 24, 2018

      @Gerbs I'm only asking because there were more than a few instances when 300BLK WAS chambered into a 5.56mm ARs and rifle went bang.

  • JohnB JohnB on Jul 23, 2018

    Awful lot of posting for THE Q. How much do you charge to advertise again? I need my product sold also.

    • @JohnB We don’t advertise like that. If you’d like a review of your product email me. No charge for reviews. If you’d like traditional advertising, I’ll put you in touch with that side of the house.

      As I explained to you in the other thread, the Honey Badger is the only gun I had for 19 days and it photographs nicely.