.300 Blackout Questions.

[aestus]

See, the hunting thing is what interests me. I want to be able to use the same rifle for multiple things and the AR platform seems to be the best choice for that. Would I be better served with the .300blk or do you guys think one of the other calibers would be better for hunting?

MoBoost - I want to get a bolt gun but that will come later. I'm looking at a Remington 700 or a Savage for that.

If I wanted a deer or hog gun and wanted to use the same mags and same bolt, then .300 blk is perfect even out of a 16" barrel. The supersonic bullets hit hard and are very accurate. If I was looking for a specialized upper purely dedicated to hunting or long distance and didn't care about having to buy a new bolt and dedicated mags, then 6.5 Grendel would be a choice. However, I would use it only for hunting and shooting long distances with it. Honestly, at that point the money would be better spent in a dedicated bolt action gun.

The .300 blk would give you flexibility as a good all round semi-auto hunting gun for deer and hogs and serve well as a self-defense semi-auto carbine to boot. Being able to run a suppressor and running subsonic rounds is just icing on the cake. Remington sells plinking ammo at about $12/box of 20, which is cheaper than what you'll find for 6.5 or 6.8. The subsonics are a bit more expensive.

If you reload, you can take .223 cases and reload them as .300 blk.

I never really saw the point in 6.5 outside of a dedicated target or hunting round. The 6.8 had merits in SBR's before the newer 77gr MK262, 75gr TSX, and the new 62gr MK318's came out in .223. Now that .300blk is out, there's almost no point to 6.8, imo.

 

[WideLoadTimmy]

If I wanted a deer or hog gun and wanted to use the same mags and same bolt, then .300 blk is perfect even out of a 16" barrel. The supersonic bullets hit hard and are very accurate. If I was looking for a specialized upper purely dedicated to hunting or long distance and didn't care about having to buy a new bolt and dedicated mags, then 6.5 Grendel would be a choice. However, I would use it only for hunting and shooting long distances with it. Honestly, at that point the money would be better spent in a dedicated bolt action gun.

The .300 blk would give you flexibility as a good all round semi-auto hunting gun for deer and hogs and serve well as a self-defense semi-auto carbine to boot. Being able to run a suppressor and running subsonic rounds is just icing on the cake. Remington sells plinking ammo at about $12/box of 20, which is cheaper than what you'll find for 6.5 or 6.8. The subsonics are a bit more expensive.

If you reload, you can take .223 cases and reload them as .300 blk.

I never really saw the point in 6.5 outside of a dedicated target or hunting round. The 6.8 had merits in SBR's before the newer 77gr MK262, 75gr TSX, and the new 62gr MK318's came out in .223. Now that .300blk is out, there's almost no point to 6.8, imo.

Fantastic info. Thanks a bunch. Happy Thanksgiving!

 

[MoBoost]

This guy is SOOOOOO full of it, I don't even know where to start ...
More energy down range with lower BC bullets.
17% increase in energy over AK47 - WTF is he smoking, and this is not the first time I hear it too! 1600ft/lb in AK vs 1300ft/lb in 300 is not exactly complicated math!

Ok, what are the "selling" points of 300?

You can run heavier bullets than 5.56 - the fact that you turn your AR into 32-20 Winchester circa 1887 doesn't seem to bother anyone.... 5.56 might not have the punch of .308, but it light years ahead in both external and terminal ballistics of 300. 5.56 case is perfect for 20-22 caliber bullets. 6 TCU, 6.5 TCU, 7TCU, 30 Whisper - keep pushing the case in wrong direction, but for a reason: knocking steel plates out of a pistol. 300 promises improvement on "live targets" - how? oh, yeah, by throwing last 50 years of terminal ballistics out of the window...

You can run 125gn super-sonic and 220s sub-sonic. Wait, did everybody just fell of the amnesia train, and forgot that different bullets require different twist rate - and being at extreme ends of the weight, so would be the twist rate. You can't have the pie and eat it too.

Last but not least ... subsonic. So you can reduce your rifle to performance of a pistol .... oversized, overwieght, overpriced pistol; color me impressed.

IThe supersonic bullets hit hard and are very accurate.

But not as accurate as 5.56 would ... and hard is rather subjective. Placement, bullet construction, velocity, caliber - 300 looses so bad on first three counts, the caliber advantage is trivial.

/hater flame suit ON

 

[aestus]

This guy is SOOOOOO full of it, I don't even know where to start ...
More energy down range with lower BC bullets.
17% increase in energy over AK47 - WTF is he smoking, and this is not the first time I hear it too! 1600ft/lb in AK vs 1300ft/lb in 300 is not exactly complicated math!

Ok, what are the "selling" points of 300?

You can run heavier bullets than 5.56 - the fact that you turn your AR into 32-20 Winchester circa 1887 doesn't seem to bother anyone.... 5.56 might not have the punch of .308, but it light years ahead in both external and terminal ballistics of 300. 5.56 case is perfect for 20-22 caliber bullets. 6 TCU, 6.5 TCU, 7TCU, 30 Whisper - keep pushing the case in wrong direction, but for a reason: knocking steel plates out of a pistol. 300 promises improvement on "live targets" - how? oh, yeah, by throwing last 50 years of terminal ballistics out of the window...

You can run 125gn super-sonic and 220s sub-sonic. Wait, did everybody just fell of the amnesia train, and forgot that different bullets require different twist rate - and being at extreme ends of the weight, so would be the twist rate. You can't have the pie and eat it too.

Last but not least ... subsonic. So you can reduce your rifle to performance of a pistol .... oversized, overwieght, overpriced pistol; color me impressed.



But not as accurate as 5.56 would ... and hard is rather subjective. Placement, bullet construction, velocity, caliber - 300 looses so bad on first three counts, the caliber advantage is trivial.

/hater flame suit ON

Bullet energy is more than what it's rated out of the barrel, but also how it performs out in distances during bullet flight. This can vary with barrel lengths and powder used and also shape of projectile. In terms of projectile shape, the 300 blk's ballistically efficient shape will overtake the 7.62x39 out at longer distances. Right now numbers are reported that about 300 meters, 300 blk will have just under 17% more energy than 7.62x39 with supersonic rounds. Yes, the video is a bit misleading because he doesn't really mention the specifics of how 300 blk can have 17% more energy than 7.62x39, despite holding less grains of powder, but that's what I believe what he is referring to. Closer than 300 meters, the difference is negligible and within 100 meters I would say that 7.62x39 would have a slight advantage. Keep in mind that most A/B comparisons are usually with 300 blk out of a short barrel vs .223 or 7.62x39 out of a longer 16" barrel.

300 blk in a 9" barrel has the same energy as .223 out of a 14.5" barrel and because of it's weight and shape can actually have a + percentage in energy than the .223 after about 300 meters or so. Now this is more due to the larger weight of the 300 blk round, since .223 has a pretty darn effective ballistic shape. The whole point of 300 blk was that it was optimized to be quiet and run reliably out of SBR'. The round was created as a non-pistol caliber replacement for pistol caliber SBR's like the MP5's and other sub guns that could be quieted down when suppressed.

300 blk uses fast burning pistol powders, which is why it's able to achieve almost 100% efficiency in shorter barrels than both .223 and 7.62x39, which both were designed to be shot out of longer barrels using slower burning powders. It's hard to do apples to apples comparisons because no matter what, you can spin the data to make 300 blk look good. This is what makes AAC's marketing of the round so effective and easy for them. If you compare 300 blk in 8" barrels vs .223 or 7.62x39 in 8" barrels, then the data weights very heavily for the 300 blk and it's a bit unfair since 300 blk was meant for short barrels. If you compare 300 blk in a 8" barrel vs 223 or 7.62x39 out of 16" barrels, then the fact that 300 blk holds it's own out of a shorter barrel vs the other two rounds in longer barrels is touted as an advantage of 300 blk's capabilities. Add in longer distances, the 300 blk ballistic efficiency will marginally overtake both .223 or 7.62x39 even out of 16" barrels. The gain is marginal but still can be used as a selling point on it's capabilities.

As for the twist rate, 1:7 twist rate is optimized 110gr - 220gr. 1:8 can be used for anything below 200. 1:9 is used for anything below 160gr. Generally, 1:7 and 1:8 twist is recommended and you can shooting anything that it out in the market. It's no different than .223 rifles (1:7 to shoot 55gr - 77gr with 1:9 recommended if you need absolute accuracy with 55gr or lighter rounds.)

The .223 was never meant to run out of short barrels. You can and they've adapted the platform to perform that role with heavier grain bullets and have addressed reliability with better understanding of gas systems and buffer weights, ect. The fact that we're able to run them in 7" and 10" barrels is icing on the cake. At the end of the day, the .223 was meant to run out of a longer barrel.

The 300 blk was built to be a quiet caliber shot out of short barrels to replace pistol caliber sub guns with a rifle caliber intermediary cartridge. The use of fast burning pistol powders means it can be shot out of a 10" or less barrel with almost max efficiency and little to no unburnt powder. This makes it a very gentle system compared to .223 when running suppressed and more reliable out of shorter barrels.

The fact that you can run supersonic rounds with a mag change, using the same gas and buffer system and still compare with the terminal ballistics of .223 and 7.62x39 is icing on the cake. Last I checked, subsonic rounds for the .223 are almost non-existant and if you do find them, they're not going to cycle reliably in your rifle without changes to your gas system and/or buffer weights, if not a total overhaul of the gas/buffer system. Also, I don't recall seeing any special subsonic 220gr 7.62x39 optimized for SBR's for sale either.

I'm really not a .300 blk fanboy, but I do like the round for it's purposes. In an AR platform, out of short barrels suppressed or unsuppressed, it's a great choice. Especially since all that it requires is a barrel change. Nothing more. Same mags, same bolt and ammo is adequately priced and there's already a decent selection of off the shelf ammo types, with more already being announced for 2013. Are there better rounds / platforms for long range accuracy? Yes. Arguably, 6.5 Grendel would be king in an AR platform and I'd pick .308 in a bolt gun for a dedicated long distance target gun.

However, in the AR platform, the cost to play vs return is huge with 300 blk when compared to 6.8 SPC and 6.5 Grendel. It just seems like a no brainer, especially if you're looking to stick with the AR platform with SBR or suppressed in mind.

I really don't get all the haterz of the round treating it as if it's the Obama of rifle cartridges and that it's prominence will forever change AR's in a bad way and make the venerable .223/5.56 go away... LOLz.

This kind of reminds me of .308 vs .223 flame wars that go on. Just replace .308 with .223 and .223 with 300 blk and that pretty much sums up every argument, heh.

 

[ASP785]

This argument comes more of a question of what 'bullet' or platform rather than 300 blackout versus .223. You cannot make absolute qualifying statements regardless of which side of the argument you are on. If you are planning on shooting the 220 grn load suppresed out of a 9inch barrel at 300 yards, you have brought the wrong tool for the job. I have no doubt any 300 black combination can hit an object at that distance, but that does not mean it is optimal. You can throw around terms like energy and terminal ballistics, but without a defined scenario or comparison you aren't comparing apples to oranges. Energy is irrelevant when the bullet trajectory looks more like an umbrella than a straight line. To quote Dr. Fackler, "An extremely important point to address is the question of velocity. Many people are obsessed with using the highest-velocity ammunition possible. This is a bad choice as penetration is usually DECREASED with increased velocity."

If I am planning on shooting at 200-400 yards, I wouldn't even consider the 300 blackout, regardless of barrel length. Its not optimal at those distances. I would choose the 5.56 every day of the week and twice on Sunday, with either a 77 grn loading or one of the Barnes TSX bullets at 50+ grns.

With that said, if I am comparing the two cartridges at distances not exceeding 100 yards out of very short <10" barrels, the gap between the performance of these two cartridges narrows. The 5.56 Black Hills 50 grn TSX loading offers amazing performance with 12+ inches of penetration through all common intermediate barriers out of short barrels. The problem is the 50 grn bullet specified by Black Hills is not available to us reloaders, which is a negative for me.

On the other hand, the 110 grn TTSX, as seen in the photos, offers greater penetration through intermediate barriers than the 5.56 Black Hills loading, and reliably expands through steel. Also it is available as a component to us reloaders, which is the main advantage for me and is why I am choosing it for an SBR platform.

The other scenario I believe the 300 blackout excels in is hog or deer hunting out of a 16" barrel based on the 30 caliber loading and the expansion characteristics of the 110 grn TTSX.

Bottom line, the 300 blackout is not the be all end all of cartridge development in the AR platform. People tout it as the do anything cartridge, because they bought in to the marketing hype. It does have its uses though.



http://ammo.ar15.com/project/Self_Defense_Ammo_FAQ/index.htm

 

[MoBoost]

Bullet energy is more than what it's rated out of the barrel, but also how it performs out in distances during bullet flight. This can vary with barrel lengths and powder used and also shape of projectile.

Wrong - once the bullet leaves the barrel only gravity, drag and gyroscopic stability matter.

In terms of projectile shape, the 300 blk's ballistically efficient shape will overtake the 7.62x39 out at longer distances.

Again, wrong - shape of the case has nothing to do with bullet flight (see above). There is indeed trivial difference in caliber (.308 vs .310) - but for sake of this discussion it is 100% negligible.

Right now numbers are reported that about 300 meters, 300 blk will have just under 17% more energy than 7.62x39 with supersonic rounds. Yes, the video is a bit misleading because he doesn't really mention the specifics of how 300 blk can have 17% more energy than 7.62x39, despite holding less grains of powder, but that's what I believe what he is referring to. Closer than 300 meters, the difference is negligible and within 100 meters I would say that 7.62x39 would have a slight advantage. Keep in mind that most A/B comparisons are usually with 300 blk out of a short barrel vs .223 or 7.62x39 out of a longer 16" barrel.

Again, this is ridicules - you can use the same darn bullet in either cartridge, one just had more boiler room and can shove the same bullet faster. Apples to apples.

300 blk in a 9" barrel has the same energy as .223 out of a 14.5" barrel and because of it's weight and shape can actually have a + percentage in energy than the .223 after about 300 meters or so. Now this is more due to the larger weight of the 300 blk round, since .223 has a pretty darn effective ballistic shape.

9" 300 125gn @ 2026FPS- 1139ft/lb w .338 BC source
14.5" 5.56 75gn @ 2627FPS - 1151ft/lb .360 BC source

Sorry, 5.56 has more energy and better bullet - 300 just can't hang.

The whole point of 300 blk was that it was optimized to be quiet and run reliably out of SBR'. The round was created as a non-pistol caliber replacement for pistol caliber SBR's like the MP5's and other sub guns that could be quieted down when suppressed.

Blackout is not optimized for nothing - it is just a blind luck consequence of 300 Whisper that 220gn bullet goes subsonic. As far as taking role of SMG - well, SMGs seem to be doing just fine with over-the-counter handgun ammunition - so why reinvent the wheel?

300 blk uses fast burning pistol powders, which is why it's able to achieve almost 100% efficiency in shorter barrels than both .223 and 7.62x39, which both were designed to be shot out of longer barrels using slower burning powders.

Again, there is nothing special about 300 blk - it is the same 20 year old cartridge just heavily marketed to general public. The difference? 300 Whisper had a specific use ... 300 BLK doesn't.

As for the twist rate, 1:7 twist rate is optimized 110gr - 220gr. 1:8 can be used for anything below 200. 1:9 is used for anything below 160gr. Generally, 1:7 and 1:8 twist is recommended and you can shooting anything that it out in the market. It's no different than .223 rifles (1:7 to shoot 55gr - 77gr with 1:9 recommended if you need absolute accuracy with 55gr or lighter rounds.)

If you start with lowered expectations in accuracy department ... what can I say...

This kind of reminds me of .308 vs .223 flame wars that go on. Just replace .308 with .223 and .223 with 300 blk and that pretty much sums up every argument, heh.

.308 offers greater energy and distance over 223 at cost of recoil and size; 300 offers ... less range and less accuracy and more recoil ... wtf?

As far as subsonic goes - as I said, SMG just do it sooooo well.

 

[MoBoost]

The other scenario I believe the 300 blackout excels in is hog or deer hunting out of a 16" barrel based on the 30 caliber loading and the expansion characteristics of the 110 grn TTSX.

You really think that .308 110 TTSX "excels" over say .224 70gn TSX traveling 500fps faster?

 

[Shadowrider]

One of these days I will have one. It will be a SBR and suppressed. I think that with the correct heavy weight bullet selection it is superior for home defense than a shotgun. Easier weapon manipulation in confined spaces, superior mag capacity, superior penetration characteristics. Very little downside that I can find when compared to a 12ga.

 

[ASP785]

You really think that .308 110 TTSX "excels" over say .224 70gn TSX traveling 500fps faster?

Excels may be a strong word...let's look at the available (limited) data to come up with a determination.

The 70 grn TSX loading will penetrate 20.55" of bare gel with 100% weight retention, 0" neck length and a recovered diameter of .432"
The 110 TTSX loading will penetrate 20.5" of bare gel. (Negligible difference), 0" neck length and a recovered diameter of .585" (.153 greater than the 70 grn, though not near enough to definitively declare a winner)

Their performance in this scenario is almost identical. The velocity difference is irrelevant. To prove whether or not it "excels" as you suggested, we would have to look at the temporary cavity length and diameter. This is data I do not have. So at this time, I cannot prove it excels at hunting compared to a 70 grn 5.56 loading. However, it certainly does not give anything up either and generally speaking, 30 caliber bullets will have a larger temporary cavity length and diameter.

The data listed above is not my own and was procured from www.ballesticstestingbbr.com.

 

[MoBoost]

The 70 grn TSX loading will penetrate 20.55" of bare gel with 100% weight retention, 0" neck length and a recovered diameter of .432"
The 110 TTSX loading will penetrate 20.5" of bare gel. (Negligible difference), 0" neck length and a recovered diameter of .585" (.153 greater than the 70 grn, though not near enough to definitively declare a winner)

Do you have velocity data for those two tests? (it is very relevant if we are looking at bare gel).