Do you hunt with a 300 blackout, is it an effective round or not?
I started shooting and hunting with the 300 Whisper before AAC was even a company. I had been watching JD for several years on other cartridges, and as a fan of all things suppressed, I took interest in the 300 Whisper when he started playing in it. But JD has proven to be his own worst enemy, and AAC had an opportunity to capitalize on that fact in launching the identical Blackout. I have a barrel for 300 blk rifle, which has since been converted to another cartridge, as well as a pistol/SBR upper in the BLK, which doesn't see as much use as my other SBR/pistol uppers in other cartridges.
Asking whether a round is "effective" or not is very open ended - you have cartridge performance on one side, and application demand on the other. If those two balance, then it's effective for the application, if they don't, then it's not. So the answer to this portion of the question is, "it can be effective for certain tasks, but is not effective for others." The same can be said for any cartridge.
There are real limitations for the 300blk which limit its effectiveness for different applications... I will say, the limitations are such, I don't really have interest in hunting with it. I'll take a 6.8SPC short barrel over a 300blk for whitetails.
If so what round do you use[?]
I tend to go cheap in my bullet choices, and haven't had any issue in doing so yet. The 110 Vmax and the 208 A-max, now ELD-M are cheap and easy to find. I load the 208 in practice 300wm loads also, so I get to do a little inventory sharing.
The TSX is a great hog and deer bullet, but like any of the monometals, it's prohibitively expensive for much volume use unless you're forced to use non-leads. I'm not, so I save money with other bullets.
[W]hat's it's affective range[?]
Effective range is going to vary with game animal, as it doesn't take as much to kill a bunny as it does a bear. If you're just killing paper, with the right optic and mount, a guy can cast it out to 1,000yrds with the super-sonic 110ish weight bullets. It drops transsonic around 500-600, depending on your bullet and barrel length (shorter in a pistol/SBR, of course), so at 1,000yrds, you gotta have a pretty dang big target.
[W]hat's the biggest game can you take?
At short enough ranges, the Blackout will kill any animal on the planet. Functionally, I'd cap it at deer, but I expect guys have, or will take baited bear and elk (at very short ranges) with it. I wouldn't say a guy has to cap it at "small bodied deer," but it certainly doesn't hurt to keep a conservative mindset with it.
It's really a 0-200yrd (for an experienced shooter) coyote, deer, & hog cartridge. It's too much bullet for game smaller than coyotes, although it could be used, and again, it's not packing enough power for bear or elk, although it could be used... A wrench could also be used to drive a nail, but that does not mean a wrench is the right tool for the job.
The challenge becomes the particular combination of high bullet diameter & weight, low velocity, and low sectional density. A 243win 110grn bullet will penetrate much better than a 300blk, even at the same velocity, due to the low sectional density of the 30cal pill, which limits the effective range of the 300 relative to its velocity - which is already low. To boost the sectional density, hunting of bigger game tends to be done with the heavy bullets, which gives better anchoring power to the bullet, but also robs you of even more velocity.
With the sub-sonics, you're talking about a 25fps ES meaning a difference of ~5" POI shift at 300yrds, and you're dropping somewhere around an inch per yard, so mis-judging by 3 yards might mean a vertical spread of 11". Not a reliable round for 300yrd shooting of game. A guy will connect on smaller targets than that, don't get me wrong, but just considering what it really means to run a sub-sonic bullet out there t0 300yrds is pretty heavy.
The lighter, supersonic bullets are still enough for deer, but they don't pack the momentum of the heavier bullets, so you're running out of power at range, even though the trajectory is easier to manage. At 300yrds, the 110's Taylor Factor is down to 7.7, whereas the 208 is hanging on to 10% more at 8.4. Might not seem like much, but remember, a lowly 243win is hanging onto 8.7 at 300yrds, a .30-06 is carrying 15.5, and a 45-70 is still touting 21.3 at 300... Really consider how well you want to anchor your game, vs how much you enjoy tracking. At shorter ranges, the 300blk has a lot of anchoring power COMPARED TO OTHER AR CARTRIDGES, but it's still an AR cartridge... No matter how many horsepower you pack into a Honda Civic, it'll never pull a semi-trailer like a Peterbilt.
Kinetic Energy doesn't mean much - it's the momentum (taylor factor = momentum x bullet dia) which really makes the difference on impact, and the 300blk just doesn't pack a very big lunchbox.
If there are any specs that are important to have in your ar rifle to be affective please share those too.
Pick your poison. If you're hunting, you'll want a free floating handguard, enough scope to select a perfect POA, a good enough trigger to not screw yourself, a long enough barrel to get the bullet up to a respectable speed AND to let you properly stabilize the rifle, and a scope with finger adjustments or a milling reticle to let you hold on POA, not holding over in space. If you keep shots under 150yrds, really under 150, life gets a lot easier.
