300 Blackout?
What’re ya, some kind of hipster?
;-)
7.62x39 is actually very close to 30-30 Winchester as far as ballistics go with the same bullet. And, if your purchasing your ammo vs reloading it, 7.62x39 is cheaper to shoot than .300 blackout. However, for shooting cheap with an AR type platform, 9mm is the way to go. But, for the 9mm AR, 100 yards is about the maximum practical range and 200 yards takes some practice. And, 9mm will shoot subsonic with 147 grain loads.
Oh, not the comparison of the 300 hiccup to the 762x39 and the 30/30.
With light bullets(125-130 grain), the 300 makes the 762 look plenty powerful and the 30/30 look like a workhorse.
The niche the 300 fits is the suppressed heavy subsonic (190+ bullets) from SBR or pistol configs.
And that fits inside the CQB/covert niche and not much else.
The 300 heavy is akin to a suppressed 45ACP in energy and useful range, but in a much more useful and accurate package.
300 light bullet carbine set ups fall under the useful parameters of just about any thing else.
But, hey, enjoy!
Thanks.
L