.300 Blackout Vs .300 Whisper

The Curious Case of 300 Blackout:  
https://www.recoilweb.com/the-curious-case-of-300-blackout-172050.html

Shades of Gray: .300 Whisper & .300 AAC Blackout:
https://www.americanrifleman.org/content/shades-of-gray-300-whisper-300-aac-blackout/
"We had to take the .300-221 wildcat concept, determine the final specs for it, and submit it to SAAMI. We did that, and called it the .300 AAC Blackout (.300 BLK)." -  Robert Silvers, director of research and development for AAC.
"Hornady .300 Whisper ammo, according to Hornady, has been specifically tested to be within SAAMI specifications for .300 AAC Blackout. If you shoot .300 BLK ammo in chambers that have a shorter or tighter throat, pressures will go up—perhaps above SAAMI maximums—so it is not OK to mix ammo." -  Robert Silvers
"... if you fire the same ammunition in two different guns and if one of those guns is tighter in the chamber, throat and/or barrel, the pressure and velocity will be higher in the tighter gun, exactly as Silvers stated above."
"Given the fact that major manufacturers such as Hornady are building ammunition headstamped .300 Whisper and recommending it for use in either platform—in addition to producing reloading dies that are marked "300 Whisper/Blackout" and Smith & Wesson stamps the barrel of its M&P-15 Whisper barrels with: "300 Whisper/300 AAC Blackout" it is safe to say that differences are minimal."

.300 Blackout Vs .300 Whisper: Is There A Difference?:
https://gundigest.com/gear-ammo/ammunition/300-blackout-vs-300-whisper-is-there-a-difference
"A subsonic 240-grain bullet is going to be going, at most, at 1,050 fps. That puts it squarely in the realm of a .45 ACP+P load. However, it does it with a carbine or pistol that holds 30-round magazines, and can be teamed with a red-dot or magnifying optic. There are even .300 Blackout and Whisper loads that offer expanding bullets"
"When fed subsonic ammo, the .300 Blackout and Whisper can use a compact and lightweight suppressor, to make them even quieter. Jumping up to supersonic loads is too much stress for the lighter, more-compact suppressors, so do be careful."
"... you can switch to .300 Blackout and Whisper loads using 110- to 125-grain bullets, which will be delivered as much as 2,300 fps out of a 16-inch barrel. For deer hunters, this is perfect."

300 Blackout vs 556: More than a Matter of Distance:
https://www.recoilweb.com/300-blackout-vs-556-more-than-a-matter-of-distance-172081.html

"At the time of writing, most 300 Blackout vs 556 comparisons use rounds fired from 16-inch barrels, which communicates some of the differences but is an odd choice considering the origins of 300 Blackout. We are mostly interested in ft-lbs of force delivered at distances under 300 yards from a 10.3-inch barreled AR-based firearm."

"... we see that in comparing 300 Blackout vs 556, the prior delivers greater force, but requires more compensation for bullet drop, which ultimately limits its effective range to about 300 yards depending on the load and optic."

"... one of the single greatest hazards is mixing ammunition. A 5.56 Nato round will likely not detonate in a 300 Blackout chamber, but the inverse can be deadly."