I've been thinking about getting a .300 Blackout upper. I like the idea of having another caliber to shoot with just an upper change and I would use it for hogs and maybe the occasional deer. I've done a bit of research but I'd like to hear some of you're opinions and experiences with it. I'm also interested in whether you have a pistol length gas system or carbine length and why. Unfortunately, I don't have a suppressor so that's not a factor.

Pistol length gas tube will function subsonic and full power loads without an adjustable gas block.

I'm a big fan of the 300 BO, particularly in shorter barrels. I have one that I SBR'd with a 11.5" barrel. Much less of a velocity drop than out of a short barrel shooting 5.56.

I also just like the recoil out of the 300 BO. Doesn't seem to be as sharp as my 5.56 AR

Finally, ammo prices seem to be getting better. Not as cheap as 5.56, but not that bad.

300 is fantastic. Pistol length on gas, but the barrel is where it gets weird. 300 seems to perform at it's peak between 8" and 12" of barrel. It works just fine in a 16" (supersonic) but it really doesn't gain much like the 5.56 will in a longer barrel. I have built a 10.5" pistol which was a very pleasant gun, and I currently have a 16" that I use for hunting (and only because I want to use a real stock on my hunting rifle - not for any perceived value in a longer barrel).

If I build another for fun - who am I kidding, I probably will - then I'll probably go short, like 8.5", with an arm brace. However, I will definitely stick with pistol gas, no matter what length.

I have enjoyed my .300BO 7.5" pistol build...it was built from the getgo as a pistol with a brace...
I have been seriously mulling over the idea of assembling a 16" carbine length upper to swap out on my rifle uppers...but at the prices of uppers from PSA it might be a better option to just buy one even without a BCG and charging handle (I've got extras )...the pistol length gas system works like a charm...

https://palmettostatearmory.co...-13-5-m-lok-fre.html

This has really been a pleasant caliber to shoot...the 123 grain super ammo from Magtech has been flawless/accurate and if you can find it on sale the price is not to spendy (plus it gives me good brass for reloading).

I enjoy it. I have the 16" Radical Firearms .300 upper with iron sights that I interchange on my rifle lower, and PSA's 8.5" .300 upper with a red dot on my pistol lower.

quote:

Originally posted by sigspecops:
I would use it for hogs and maybe the occasional deer.

For hunting use, consider a longer (i.e. non-SBR) barrel.

I have an 11.3" blackout barrel. A good hunting bullet is found in Barnes Vortex TAC-TX loads; for grins I'll use the 110 grain load. I get a muzzle velocity of 2,350 fps, which translates to 1,350 foot pounds of energy.
At 100 yards (at 4,000 feet Density Altitude) the kinetic energy drops to 1,081 foot pounds.
At 200 yards the kinetic energy is down to 857 foot pounds.

Going to a 16" barrel, the muzzle velocity should increase to about 2,520 fps, which is 1,551 foot pounds of energy.
At 100 yards the kinetic energy is 1,252 foot pounds.
At 200 yards the kinetic energy is 999 foot pounds.

These are not trivial energy increases. If hunting is your primary focus, the additional barrel length leads to increased MV, which leads to more kinetic energy for a cleaner kill.

Understand that many 30 caliber bullets don't expand well at the pokey velocities of the blackout cartridge. More velocity will assist the bullet in doing its job.

fritz is spot on with his numbers.

quote:

At 200 yards the kinetic energy is 999 foot pounds.

for hunting, consider this - that number posted is higher at 200 than a 44 mag is at the muzzle of a 4" revolver.

So for hunting purposes, the extra barrel and being able to use a real stock without a stupid stamp may well outweigh the advantages of less weight and a smaller overall package.

If you are a hand loader the 300 BLK is a playground for breadth of projectiles and powder.

In my RARR, the current 'hunting' load is with the Speer 150gr Gold Dot on top of a compressed load of 1680. Making ~2150 fps, 100 yard 3 shot strings all 3/4" or less. If I were shooting from a stand and range was less than 100 yds, my 10.5" pistol would get the nod. In MT we can hunt with suppressors, so this adds to the pleasant shooting little cartridge. The Gold Dot BLK version expands nicely down to 1400 fps and will be a good hunting bullet.

I have an 8" SBR with a pistol length tube, never a hiccup. That said, for hunting my go to is 6.5 Grendel. With popularity increasing and wolf loading it cheap there isn't a ton of reasons to go 300 if you aren't shooting suppressed.

I am a Blackout NUT and would have to review my records to see how many I have (around a dozen AR uppers, both action and single shot). Been doing Blackout bbl wear testing for years now and hunt every year with the cartridge. That having been said...

A lot of good info in the replies so far.

It is "made" for hand loading in my opinion, with such a plethera of bullets out there. Can even make your own brass if you want. For example, I do a lot of subsonic and supersonic shooting with WWII M160 108gr frangible bullets for very cheap shooting. I also do a lot of cheap shooting with pulled 123gr 7.62x39 fmj bullets.

For hunting over 100yd, I agree that 16" is the way to go. For example, the Nosler 125gr Ballistic Tip needs 1800fps for "optimal" expansion per Nosler. That means a 16" bbl is good for about 200yd, a 9.5-10.5" bbl is 150yd, and 8" or shorter are 100yd if using that bullet. The Barnes 110gr blacktips expand at lower velocity, but I still want velocity for penetration and energy. Note: The Barnes gives about 2" more penetration on boar hogs over ~150 pounds than the Nosler. On sows it doesn't matter. When I deer hunt with my goats, I carry a suppressed SBR for handiness and the short distances involved.

Have taken 21 deer, 16 hogs, and 4 coyotes with Blackouts.

I've never worried about the gas tube length vs bbl length, figuring the bbl makers would not normally build a combination that didn't work...I've had no problems regardless of the gas tube length, but would recommend a pistol length gas tube...it'll work for sure, especially subsonic.

As far as bbl material (416R, 4140, and 4150/41V50), bore treatment (nitride, chrome lined, or none), or bbl rifling forming (button rifled or CHF), buy what YOU feel good owning. Bbl life to most owners will not matter for the Blackout. Shortest calculated life is plain 4140, button rifled, no bore treatment, about 11,000 jacketed rounds fired slow fire in my testing until the throat has advanced 1" from new. Each item beyond that adds more rounds of life, going up to the "ultimate" of 4150/41V50, CHF, double chrome lined, which my testing indicates should be good for about 22,000 jacketed rounds. For example, CHF over button rifled adds 500-1000 more rounds in 4140 steel; nitride adds more life; chrome lining adds more; 4150 wears slower than 4140. (Figures are based upon throat wear so far.) And FWIW, although some people say nitride lasts longer than chrome lined, in my Blackout testing, chrome lining is lasting longer than nitriding. However, nitrided Blackout bbls are more common than chrome lined. Again, for most folks, don't worry about it.

Accuracy?...you just never know. My most accurate Blackout bbl, bar none, is a Daniel Defense bbl, yet another DD Blackout bbl is of "average" accuracy...go figure. I don't mean to imply the 2nd DD bbl is not accurate, it's just that 2 bbls from the same maker using the same steel and making technique give different results.

This year I took an 8pt at 98yd with my Ruger SR556 Takedown with Blackout conversion bbl and Barnes 110gr blacktips. Using my Ruger American Ranch Rifle, same bullet, I took a 7pt at 140yd. Both double lung shots. Both deer went about 40yd and dropped. I can never make up my mind which rifle, so I take 3-4 Blackouts and carry a different one each trip to the hunting field. Variety, the spice of life. Oh, my deer, coyote, and hog hunting is all supersonic suppressed. Doesn't bother the animals as much, ring my ears, can sometimes hear the bullet hit or the deer drop, can sometimes get multiple shots, and doesn't bother neighbors when I'm doing hog control at a nearby farm. For armadillo control, I shoot subsonic suppressed frangible bullets...doesn't bother anybody but the dillos.

I have an adjustable gas block on one upper. The gas port of that bbl is drilled a little bigger so in combo with the gas block it will function with a wider range of loads, probably outside of the range of most shooters. Thus, I don't see the need for an adjustable gas block for most folks.

quote:

Originally posted by Dae Zee:
I am a Blackout NUT and would have to review my records to see how many I have (around a dozen AR uppers, both action and single shot). Been doing Blackout bbl wear testing for years now and hunt every year with the cartridge. That having been said...

Great post!

What buffer weights do you use? My first .300 gun is a pistol 8.3" 1:7 with one of these.
https://ballisticadvantage.com...-premium-barrel.html

It's also my first completely-from-scratch AR build. I've shot it a bit to make sure it works, but I'm waiting for my suppressor to get out of jail and will feed it a variety of factory loads to get it dialed in. Curious if I'll need to tune the buffer weight or what your experiences might be.

Thanks for the info and opinions, all of this really helps.

Delayed reply...recovering from surgery.

What buffer? When I first got into the Blackout, the "IN" thing to use was a heavier buffer, so my 1st 2 Blackout lowers (SBR used with 10.5" and shorter bbls) used and continue to use the Spike's T2. One lower has had 17992 rounds fired and the other has been fired 6165 rounds. At 16000 rounds I did replace the buffer spring, as it now measured the minimum length. Since then I've bought or built other AR lowers and have carbine, H1, and H2 buffers. Blackout uppers range from 8" to 16" and are mostly shot suppressed, subsonic and supersonic. I CAN TELL NO DIFFERENCE IN ACCURACY, FUNCTION, OR PARTS BREAKAGE/WEAR BETWEEN THE BUFFERS IN MY NOW WELL OVER 20,000 ROUNDS OF BLACKOUT FIRED.

Maybe I've just been lucky, as I've only had one Blackout upper that acts bizarre. In it, only when using the Barnes 110gr black tip bullets, the 1st round out of the mag consistently hits low. Bbl cold or hot, suppressed or not, every buffer weight tried, multiple mags tried, rounds ejected and checked for damage, different lowers, etc, etc. Oh well, I just use Nosler 125gr BT in that upper with fine accuracy.

I just bought a Springfield Armory Saint AR pistol in 300 BLK from Buds. Looking forward to getting my hands on it.

It’ll be my first experience with 300 Blackout.