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Thoughts on the staying power of 8.6 blackout? Is it around to stay? Do you think Hornady will offer an alternative that will replace it?

LilGucci

Gunny Sergeant
Full Member
Minuteman
Oct 7, 2019
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I tend to build my rifles from receiver sets, but I want to buy a complete rifle and I was looking at 8.6 blackout. Do you all think it has staying power? Only because I don't intend to reload my own ammo so I'm going to rely on buying factory ammo. Do you see Hornady offering an alternative to 8.6 like they did with their 338 Arc as an alternative to 300blck out?

My intentions for this rifle is to be a short barrel rifle that is fired suppressed. I'm considering 300blkout, 338 Arc, and 8.6. My attraction to the 8.6 is that it's a caliber for a large frame rifle, and it would be nice to have a large frame SBR that shoots quietly since I don't have that in my collection. Also... I have like 3 AR15's in 300blk out, a few non AR's in 300blkout, and I will be getting 338 ARC guns soon too.
 
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The 8.6 Blackout is a difficult caliber to like, especially in its 3 twist form, it's very limited with lead and expensive to shoot because for supers ya have to use all copper bullets, so they don't explode soon as they leave the co fines of the barrel.
Damaging your muzzle device and magneto speed bayonet chronograph.

I spent thousands on it. Took off the 3 twist Faxon it was a galled and torn rifled barrel, with horrible accuracy in the AR 10.

Bought a 6.5 twist and chambered it for 8.6 blackout for Rem 700 bolt gun.
This was a much better combination.
Cheap lead bullets can be used as fast as your rifle can shoot them. No problem with any bullet blowing up with the 6.5 twist...unfortunately most barrels are the horrible 3 twist.

The problem with tbe 8.6 Blackout is that it has too much case capacity for subsonic shooting and too little for supers. A compromise that is made worse with the 3 twist and its dangerous limitations with respect to muzzle velocity on jacketed lead and some copper specialty bullets.

If you go with the 8.6 blackout you must be a reloader. And buy a special made 6.5 twist barrel for your rifle to get accurscy and full potential out of this cartridge.

Case for the AR 15, light weight, better accuracy with the slower twists, and does the same job with subs.

I have a 338 Spectre which is almost the same as the 338 ARC.
Hornady calls the 3 twist on the 8.6 blk ridiculous...I agree. They use an 8 twist on the 338 ARC.
The 338 Spectre has a 6.5 twist, which has been excellent for me...but I believe the 8 twist will do fine in the 338 ARC.

So my advice especially if your gonna shoot factory loads, mostly subs. In short barrel suppressed, go with the 338 ARC, ammo already available. It will be more accurate and more consistent in velocity, important as your range increases with subs.

Check out the 338 Spectre if you reload, as factory loads are very limited.


Pic of 338 spectre the slightly shorter length vs the 338 ARC. These two are better performing cartridges for subs, excellent accuracy and low velocity spreads.
The 338 Spectre every bullet has been accurate from 160 gr Barnes supers to 350 gr Maker (handloads) with single digit standard deviations...this should be very similar to what the 338 ARC will do.
 

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The 8.6 Blackout is a difficult caliber to like, especially in its 3 twist form, it's very limited with lead and expensive to shoot because for supers ya have to use all copper bullets, so they don't explode soon as they leave the co fines of the barrel.
Damaging your muzzle device and magneto speed bayonet chronograph.

I spent thousands on it. Took off the 3 twist Faxon it was a galled and torn rifled barrel, with horrible accuracy in the AR 10.

Bought a 6.5 twist and chambered it for 8.6 blackout for Rem 700 bolt gun.
This was a much better combination.
Cheap lead bullets can be used as fast as your rifle can shoot them. No problem with any bullet blowing up with the 6.5 twist...unfortunately most barrels are the horrible 3 twist.

The problem with tbe 8.6 Blackout is that it has too much case capacity for subsonic shooting and too little for supers. A compromise that is made worse with the 3 twist and its dangerous limitations with respect to muzzle velocity on jacketed lead and some copper specialty bullets.

If you go with the 8.6 blackout you must be a reloader. And buy a special made 6.5 twist barrel for your rifle to get accurscy and full potential out of this cartridge.

Case for the AR 15, light weight, better accuracy with the slower twists, and does the same job with subs.

I have a 338 Spectre which is almost the same as the 338 ARC.
Hornady calls the 3 twist on the 8.6 blk ridiculous...I agree. They use an 8 twist on the 338 ARC.
The 338 Spectre has a 6.5 twist, which has been excellent for me...but I believe the 8 twist will do fine in the 338 ARC.

So my advice especially if your gonna shoot factory loads, mostly subs. In short barrel suppressed, go with the 338 ARC, ammo already available. It will be more accurate and more consistent in velocity, important as your range increases with subs.

Check out the 338 Spectre if you reload, as factory loads are very limited.


Pic of 338 spectre the slightly shorter length vs the 338 ARC. These two are better performing cartridges for subs, excellent accuracy and low velocity spreads.
The 338 Spectre every bullet has been accurate from 160 gr Barnes supers to 350 gr Maker (handloads) with single digit standard deviations...this should be very similar to what the 338 ARC will do.
I can't thank you enough for this. It was so thorough. You covered so much in it. I think I'll stick to 338 ARC for my next purchase then.
 
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I can't see it getting big like 300BO for several reasons. First is there is a lot of development that has produced good hunting subsonic bullets in 300 BO. I question if a 338 will get results noticably better, or if bullet makers will put in the effort with such a small market.

Second issue is practicallity, costs more to shoot, needs 338 suppressor, etc. I think most people will start with 300BO and only a tiny group would want to go beyond.

Assuming the main market here already has a 300BO, 8.6 is not the only choice. I went 458 SOCOM AR-15 over 338 Specter long before the 8.6 was out. There are bigger kids on the block, lever guns, bolt guns etc. crowded market space and small.

My 458 SOCOM is in the same boat. Love it, but it will never get a date to the prom.
 
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I've debated a 8.6 build .....paused it for all the reasons mentioned above.

If 6.5+ twist starts becoming a product offered by most barrel mfgs as an off the shelf option....maybe it stays long term....if not I'd say the chance of it fading is significantly higher.

As far as reloading......it may seem daunting and yes takes time.......but I would recommend spending money on reloading tools, powder, primers and bullets for pew pews you already have vs spending that money on an 8.6 rifle.

Everyone has their own thoughts and logic, I'd rather have the capability to reload several thousand rounds for tools already in the safe vs having a useless paperweight 8.6 rifle if things ever went south
 
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Not trying to bash your ideas, it's a free country and do as you please.

Here's food for thought when money's literally worthless and nobody is coming to help.

Imagine how much better off you'd be with the capability to reload in this situation......I'd also add that owning the night would be a level above most

 
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Now here's where I like the 8.6 Blackout.
Its mostly in the supersonic realm.
IF ya go to the 6.5 twist and longer barrel, add hybrid cases its a power house.
My favorite general purpose load is 200 gr Speer at 2600 fps.

But since I waste a lot of ammo, and decided to try some factory 2nds and pulled bullets.

American Reloading has the 272 gr FMJ on sale .30 each shipped and 300 SMK pulled for .56 ea shipped.
Bought 500 ea to try.

The 272 gr I got were good to go as the arrived ... the 300 gr SMK need to be sized.
Pull marks mess up the OD.

Made a sizing die and sized them all. One could use Lee bullet sizing die in .338" but I made mine .3378" to get the pulling dings out so they seat nice in the case.

The Sierra factory 2nds were .47 ea no sizing needed.

I shot alot of the 272 gr FMJ and find accuracy typical of most FMJ bullets, good for plinking, but not the best in accuracy.

Sized 300 SMK. Running through the homebuilt die.
Factory 2nds from Sierra are not pulled bullets no sizing necessary.

Next 272 FMJ subs

Next resized 300 gr SMK supersonic load.
Which shoots good in my rifle.
DO NOT shoot in 3 twist this is a high velocity load for bolt guns and 6.5 twist.
It hits the target hard and has a fair amount og recoil, as it tends to knock over the target, when shooting steel.

Just for informational purposes on what might work for you getting the cost down when shooting the 8.6 Blackout.
My choice is stay with the 300 gr match bullets, and use factory 2nds or pulled resized seem to be accurate, as shown.
 

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I can't see it getting big like 300BO for several reasons. First is there is a lot of development that has produced good hunting subsonic bullets in 300 BO. I question if a 338 will get results noticably better, or if bullet makers will put in the effort with such a small market.

Second issue is practicallity, costs more to shoot, needs 338 suppressor, etc. I think most people will start with 300BO and only a tiny group would want to go beyond.

Assuming the main market here already has a 300BO, 8.6 is not the only choice. I went 458 SOCOM AR-15 over 338 Specter long before the 8.6 was out. There are bigger kids on the block, lever guns, bolt guns etc. crowded market space and small.

My 458 SOCOM is in the same boat. Love it, but it will never get a date to the prom.
For hunting the larger the bore diameter the larger the wound channel will be if bullets of the same construction are employed at subsonic velocities.
Kinda like muzzle loaders back in the day, where .36 cal was considered a squirrel gun.

Hornady has introduced the 338 ARC, almost identical to the 338 Spectre, and making 307 gr subsonic bullets for it.
Plus Maker has a variety of 338 hunting sub and super bullets for 338 caliber 165 gr to 350 gr.
A potentially better killer than the 300 blkout.

I like the 45 calibers for the same reason, limited to 1100 fps.
I use the 450 Bushmaster with a 16 twist, so I can use cheap bulk 45 cal pistol bullets for high velocity plinking, Hornady 395 gr sub bullets .452,... or resized .458 bullets of any weight to the jacketed 500 gr or cast 502 gr.
The 450 bushmaster is an excellent caliber for sub/ super close range hunting, or plinking fun.
But it's general accuracy and consistency are not up to my 338 Spectre, but that's not need in close range encounters with big game.
I was going to put thr 510 whisper on an AR 10 but it was too limiting with long 50 cal bullets.
But the AR 15 510 whisper could be utilized with the short 300 gr Barnes .510 for supers at 2300 fps or more in a 16" barrel at low pressure with 87 grs of powder capacity, for around 3600 ft-lbs of muzzle energy.
So I had to see if it is possible, and yes it is, but would require quite a bit of machining
The 450 bushmaster mags will work with some machining, and so will the brass... cut the solid head down and new extractor groove cut.
Now you have .510 cal AR 15 but only for short bullets, 300 gr soft point supers to 350 gr copper subs .510 HG Lehigh Defense bullets that expand at 900 fps.
But you'd have to machine a 16" AR 15 barrel from a blank, with a 450 bushmaster barrel extension.
I have the 510 whisper reamer, I could do that.
Anyone interested, besides me.
 

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