8.6 Blackout accuracy and barrel twist

Yes, typical Faxon 3 twist, mine was maybe worse...chunks of metal were torn off the rifling. Appeared fuzzy looking down the bore, ran a patch through it, and it was brown with slivers and small pieces of metal from the bore...So I lapped it before I shot it.. it still had chunks of metal missing in the beginning by the chamber, but was better toward the muzzle.
It all sounds very familiar. There are parts of the barrel that looks even worse than in the pictures I posted.

8.6 Blackout with a 6.5 twist is kind of just a 338 whisper with a lite bitt bigger case volum. I'm probably ending up going the same route as you in the end since i already have 8.6 brass and tooling? But there will be no more Faxon for me....ever.. I didn't have high expectations but this was a new low.
 
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Your first two pic's are damage to the rifling from when the button was pulled thru. Button rifling with these really fast twist I feel will always be an issue. Button rifling displaces the material it doesn't remove the material. Depending on the spec of the button and the material as it will always change they might be pulling a .341" to .342" button size for the groove down the barrel in order to end up with a .338" groove size. Like a snake swallowing a mouse. The steel will expand and spring back where we physically cut the grooves. Those edges of the lands is what we call tearing/tore. It could be a soft spot or a hard spot in the material and with that really fast twist and the conventional rifling it's tearing/breaking chunks out of the edges.

When we cut rifle the barrels we are only cutting like .0001" per pass. Basically shaving.

Also that hard edge of conventional rifling isn't going to help with the button process. That hard sharp edge is going to take a beating.

Your 3rd picture those are bore reamer marks (assuming they are reaming the bores before pulling the button thru as some shops/gun makers to save time and money will go from drilling the blank to just pulling a button thru but those look like bore reamer marks) on the lands and in the grooves. Again button rifling displaces material and the rougher that finish is from the bore reamer... the button is just going to push them down into the grooves as well.

Again the rougher bore/grooves like that and any damage to the edges of the lands.... means the bullets will take more of a beating/get damaged done to them and then the really fast twist rate isn't going to help anything at all either. Accuracy will suffer and bullets blowing up will be another.

That hard edge of conventional rifling will also leave a burr on the sides of the bullets. It will look like a flag sticking up on the side of the jacket. I've seen those burrs as big as a 1/32" of an inch and that will affect the bc of the bullet and affect the flight of the bullet as well.

Later, Frank
Bartlein Barrels

Frank

Thank you very much for taking the time to drop knowledge like this on us laypersons.
 
Yeah, I noticed that too when I first saw that video...however...it's really hard to tell from video if that is not an artifact of lens distortion or sensor distortion as a consequence of "rolling shutter" (the readout time from the camera sensor top to bottom is linear, so over a period of microseconds it results in angular distortion of moving objects in the direction of their motion). Point being...I'm not sure...it does seem odd that a bullet spinning that fast would start to nose up (or ass down) just a few inches out of the barrel...so...inconclusive in my view...

The thing I care about most at this point is suppressability...if that's a word...I want a powerful subsonic round that is as quiet as possible. What else besides 8.6 achieves that? .458 socom is pretty impressive...but the ballistics are more challenging than 8.6...


Funny you mention the 458.
I've recently been running (another) thought experiment about what the optimum subsonichunting cartridge is, and came up with the 458 SOCOM.

The biggest issue with the 8.6BLK IMO is the lack of expanding subsonic projectiles. Yes it beats out 300BLK or 308 by having bigger heavier projectiles thus much more energy but still lacks the proper big bore cartridges.

I'm well aware there are a variety of subsonic projectiles butthey are all crazy expensive and basically force you into having a dedicated hunting load that you sure as hell won't be pilinking with.

If subsonic hunting is the main use case then I think something that'll shoot pistol projectiles is the way to go.

If you want to shoot a mix then I still think 308 is a better choice than 8.6BLK, with the caveat of a more limited selection of powders to choose from.

I'm ready for the flaming to begin, but the video above sure shows the 458 SOCOM is a worthy competitor to the 8.6BLK.
 
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For the fun of it I tried shooting a statistically representative grouping with the barrel from Faxon.
I don’t know what people manage to shoot with 8.6BLK @100 meter? There is not much information to find regarding expected precision with 8.6BLK looking at the web. But this group is absolutely useless;
IMG_0347C3DB5495-1.jpeg
 
Yeah, I noticed that too when I first saw that video...however...it's really hard to tell from video if that is not an artifact of lens distortion or sensor distortion as a consequence of "rolling shutter" (the readout time from the camera sensor top to bottom is linear, so over a period of microseconds it results in angular distortion of moving objects in the direction of their motion). Point being...I'm not sure...it does seem odd that a bullet spinning that fast would start to nose up (or ass down) just a few inches out of the barrel...so...inconclusive in my view...

The thing I care about most at this point is suppressability...if that's a word...I want a powerful subsonic round that is as quiet as possible. What else besides 8.6 achieves that? .458 socom is pretty impressive...but the ballistics are more challenging than 8.6...


This is an older Smarter Every Day video where he captures a bunch of high speed footage looking for shockwaves. One of the subsonic shots clearly shows the bullet nose up plowing through the air. Pretty cool stuff. He's done a bunch of gun vids.


Same guy

 
I haven't double checked the math, but I thought this article was interesting.

https://kurtthegunsmith.com/8-6-bla...ew-subsonic-338-and-how-it-actually-performs/

I don't think the writer figured the "twist energy" into the equation, but if you calculate energy the usual way then it looks like the Raptor pulls ahead a bit.

I got the chance to visit with Arne Brennan a bit, and we agreed that the Raptor simply strikes a balance of compromises. You can fire a big slug of copper subsonic or you can shoot light-ish for caliber bullets supersonic.

We talked a bit about bullets and Arne liked the 270gr Speer. Simple and affordable. I like to play around, so I wanna try various monometal designs.

I would try the 8.6BLK, but maybe not a 1 in 3 twist. I don't mind new cartridges. The hype gets a little old, though.

Also, in watching the videos above, I didn't even think about supersonic flow over a subsonic bullet. It seems more pronouced on the topside of the bullet which I believe would make sense if it is flying with a nose-up attitude.
 
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Funny you mention the 458.
I've recently been running (another) thought experiment about what the optimum subsonichunting cartridge is, and came up with the 458 SOCOM.

The biggest issue with the 8.6BLK IMO is the lack of expanding subsonic projectiles. Yes it beats out 300BLK or 308 by having bigger heavier projectiles thus much more energy but still lacks the proper big bore cartridges.

I'm well aware there are a variety of subsonic projectiles butthey are all crazy expensive and basically force you into having a dedicated hunting load that you sure as hell won't be pilinking with.

If subsonic hunting is the main use case then I think something that'll shoot pistol projectiles is the way to go.

If you want to shoot a mix then I still think 308 is a better choice than 8.6BLK, with the caveat of a more limited selection of powders to choose from.

I'm ready for the flaming to begin, but the video above sure shows the 458 SOCOM is a worthy competitor to the 8.6BLK.
the 400gr the 375 rap slings is an expanding subsonic, works similar to the lehigh controlled chaos and creates three 'petals' that cut like a corkscrew. While the muzzle energy is less than a 675gr .458 SOCOM, it preserves the energy better over distance because of the projectile shape, leading to better terminal performance. Just something to consider.
 
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In my head I can’t see that the extra bullet rotational inertia itself transfers a drastically more energy into a gel block or tissue. What does make sense is that a bullet on the ragged edge of spinning apart in flight will open extremely quick and easily on target.
 
The extra rotational energy is very small contribution to total energy, like 20 ft/lbs. Shot to shot velocity variations add or subtract more or less energy.
Ask for the mathematical computations of the energy increase for a 3 twist over a more reliable 6.5 twist....absolutely no affect on killing power.
I own the 3 twist, and find it's very unimpressive, not accurate, very limiting, and dangerous...such a negative I'm changing to 6.5 twist on my 8.6 blackout...I too had to try it out, just to see, and do not recommend it ...Faxon will not change it as they are under licensing agreement...I asked ...told em I'd eat the 3 twist and buy a new 7 or 8 twist..they could not do that per licensing agreement.
 
Energy doesn't really answer everything either. For the bullets that really open up big it's not hard for me to believe that the extra rotational speed could do quite a bit of damage. Like a little blender.
 
It seems like its just another brittenham program to copy something that works and screw it up. He and his buddy silvers copied the 30-221 or 300 whisper but changed a few things to make the supersonic loadings less inaccurate but that screwed up the subsonic accuracy. The 300 blackout isn't worth a crap.

Why add the case capacity to a cartridge like the 338 BR which has been around forever and the 338 whisper which JD jones copied from the BR? When you're planning subsonic as the primary use extra capacity is useless. In addition to that the whole superfast twist thing just screws it up more.

I'm sticking with the 338BR which is based on the 30BR or 6.5mm BR necked up to 338. Its a shortened 308 case essentially with a small rifle primer. Running the 300 gr bullets you're looking at about the same powder and charge weight as the 8.6 and the same velocity but with less case overcapacity you're getting a more consistent burn and better accuracy. A twist rate of 1-8 has been standard for years and works great. Going to 1-7 doesn't seem to help or hurt but neither twist rate requires special tooling just to avoid peeling metal off the bore.
The idea that more energy is delivered by spinning things way too fast is crap in real life. It also means you have to put that energy in there in the first place if you really mean to get it out. I believe you're just pushing things past their useful limits.

All in all the 8.6 appears to be the endpoint of a marketing mans ad program. Sell them on the idea and they'll buy the product. Once they've bought it they'll defend it against detractors because they don't want to be seen as idiots. There were already cartridges out there that did the same job and in many if not most cases they do it better. The problem is brittenham wasn't collecting the cash from them....

Just my thoughts based on years of playing with the 338BR and other subbies.

Frank
 
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It still cracks me up when people talk about the 300 Blackout like it was a bad idea or failure. It's a lot like the people that call the Creedmoor manbun or similar. Really just shows ignorance about what is involved in rolling out a successful cartridge. 300 Whisper could have been the pick but ole JD had no desire to let his calibers go. He could have done the work that Kevin did and got together big manufacturers like Hornady and arranged SAAMI approval. We could have had a 10-15 year jump on Whisper standardization and it could have been in place when the commercial interest in subsonics and suppressors went ballistic but alas it took Kevin to do it.

The whole point of 8.6 Blackout is not subsonic it's the ability to do both just like the 300. Kevin stated numerous times that you would be better off with something like the 338 Spectre if all you want is subs.
 
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How many guns and ammo variants are available for that? Could have just done a 375 Whisper
anything that will take standard .308 can run it without much issue, mags are standard metal .308, pmags can be used by filing a couple thousandths off the front reinforcing rib.

bolt face is standard .308, so is the case head.

gas systems generally play nicely as the cartridge was designed from the ground up to be used in those platforms

bullets there are some specific ones designed by maker bullets, but most of the ones designed for .375 H&H/weatherby/etc will work


I’ve been enjoying mine for some time now.

edit: Bonus: you can legitimately call it your elephant gun because it meets african game legal minimums of .375 or larger :ROFLMAO:
 
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My point was that nobody makes them. That website throws flags and has been dormant for a long time. Almost no components available so you have to make brass. I looked into 45 Raptor a while back but like to stick to mainstream stuff for the most part.
 
anything that will take standard .308 can run it without much issue, mags are standard metal .308, pmags can be used by filing a couple thousandths off the front reinforcing rib.

bolt face is standard .308, so is the case head.

gas systems generally play nicely as the cartridge was designed from the ground up to be used in those platforms

bullets there are some specific ones designed by maker bullets, but most of the ones designed for .375 H&H/weatherby/etc will work


I’ve been enjoying mine for some time now.

edit: Bonus: you can legitimately call it your elephant gun because it meets african game legal minimums of .375 or larger :ROFLMAO:
I'm not saying I disagree but it looks like with 375 Raptor you still run into issues with projectiles like you do with 8.6BLK.

For the most part the projectiles are very similar weight between .338 and .375.
You still are reliant on expensive turned copper bullets.

I can't help but shake the thought to have a true best alrounder for subs and supers you need a cartirdge that'll shoot pistol bullets that'll expand at subsonic velocities.
 
Energy doesn't really answer everything either. For the bullets that really open up big it's not hard for me to believe that the extra rotational speed could do quite a bit of damage. Like a little blender.
It doesn't work like that, the bullet doesn't stay in one place and spin around. So a total of 4 revolutions through 12" or 2 revolutions it doesn't matter, neither will not whip your egg whites...then it could tumble, causing more damage than the spinning effect.
30 cal Speer Varmint bullets fired sub sonic in a 7 twist 300 blackout and no expansion at all perfect, just the rifling. Put the same bullet in a 12 twist double the velocity or a bit more, the bullet blows up completely. Spin is for stabilization of the projectile, that's all, nothing more of consequence is added to the equation.
Ask for the mathematical proof...if you have any doubts.
 
I'm not saying I disagree but it looks like with 375 Raptor you still run into issues with projectiles like you do with 8.6BLK.

For the most part the projectiles are very similar weight between .338 and .375.
You still are reliant on expensive turned copper bullets.
no? my supersonic load uses the 260gr nosler accubond, while the subs are using 300gr speer SPBTs that don’t run the risk of spinning apart. if you want maximum subsonic performance the maker 400gr monolithic expanders are available, but the speers have done just fine on the deer and hogs I’ve shot with them

edit: for reference, .375 Raptor only needs a 1:8 - 1:10 twist rate, as the projectiles for a given weight are much shorter than 8.6, so require less spin to stabilize
 
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It doesn't work like that, the bullet doesn't stay in one place and spin around. So a total of 4 revolutions through 12" or 2 revolutions it doesn't matter, neither will not whip your egg whites...then it could tumble, causing more damage than the spinning effect.

This is not necessarily accurate, given what we know about tissue damage.

Lacerations through tissue reduce the elastic limit of the tissue. This is shown by Fackler’s studies.

Sure, the bullet isn’t going to whip up tissue exactly like a blender, but it will result in a greater exchange of temporary stretch to permanent wound cavity as it will be easier to exceed the elastic limit of more tissue along the path. Tumbling is great to transfer energy ( essentially representing a larger meplat), but it doesn’t necessarily mean a larger permanent wound channel. If that energy transfer doesn’t create a large enough temporary stretch cavity to exceed the tissue’s elastic limit, then it doesn’t help much. Reducing the elastic limit is from fragmentation, or potentially a faster twist with a large opening solid copper.

I’m not a fan of Brittingham, and wish 375 Raptor got industry support instead, but I’m not going to pretend to be blind to potential wound mechanism benefits of a faster twist. Do those benefits outweigh the cons of being limited to expensive solid copper bullets and barrel manufacturing difficulties/expenses? That’s up to the shooter.
 
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no? my supersonic load uses the 260gr nosler accubond, while the subs are using 300gr speer SPBTs that don’t run the risk of spinning apart. if you want maximum subsonic performance the maker 400gr monolithic expanders are available, but the speers have done just fine on the deer and hogs I’ve shot with them
No issues with expantion at subsonic velocities?
what powder do you use in your sub loads?

I played with 300blk for a while (should've kept it longer) but wasn't impressed with the performance I was getting with cast lead bullets.
I'm wanting to find a cartridge that'll work for both subs and supers, that I don't need to mess around with flaring case mouths for cast bullets or paying crazy amounts of money for copper projectiles that I cant plink with.

But if it wasn't for trail boss being unobtanium I'd just go with 308 and call it a day.
 
No issues with expantion at subsonic velocities?
what powder do you use in your sub loads?

I played with 300blk for a while (should've kept it longer) but wasn't impressed with the performance I was getting with cast lead bullets.
I'm wanting to find a cartridge that'll work for both subs and supers, that I don't need to mess around with flaring case mouths for cast bullets or paying crazy amounts of money for copper projectiles that I cant plink with.

But if it wasn't for trail boss being unobtanium I'd just go with 308 and call it a day.
I have a 300blk 9" MCX I enjoy, and instead of cast lead the hornady sub-x has been quite excellent in my gel tests. readily available factory and for reloading.

I mostly use Tin-Star for subsonics, but have been playing around with some other powder options. it's a pretty forgiving envelope and case, so there is room to work with a few different options. Never had the soft points fail to expand on a good shot, they do what you'd expect a jacketed hunk of lead to do and mushroom out. the 400gr Makers are nastier, but imo actually did too much damage to the hog I shot with one, wasted a bunch of good shoulder.
 
I have a 300blk 9" MCX I enjoy, and instead of cast lead the hornady sub-x has been quite excellent in my gel tests. readily available factory and for reloading.

I mostly use Tin-Star for subsonics, but have been playing around with some other powder options. it's a pretty forgiving envelope and case, so there is room to work with a few different options. Never had the soft points fail to expand on a good shot, they do what you'd expect a jacketed hunk of lead to do and mushroom out. the 400gr Makers are nastier, but imo actually did too much damage to the hog I shot with one, wasted a bunch of good shoulder.
I never got around to testing the Sub-X on game, but they shot well on targets.
I few people I knew tried them on small-medium game and had less than stellar results, basically seemed like copper bullets were the only safe bet on game.

If the .375 Speer SPs work well at sub sonic speeds I wonder in their 30cal and 338cals work equally as well?
Not many people seem to use the ol soft point these days so maybe they just haven't been tested as much as the new wizz bang projectiles.
 
no? my supersonic load uses the 260gr nosler accubond, while the subs are using 300gr speer SPBTs that don’t run the risk of spinning apart. if you want maximum subsonic performance the maker 400gr monolithic expanders are available, but the speers have done just fine on the deer and hogs I’ve shot with them

edit: for reference, .375 Raptor only needs a 1:8 - 1:10 twist rate, as the projectiles for a given weight are much shorter than 8.6, so require less spin to stabilize
Speer doesn't make a 300 gr SP only a 270 gr, & 235gr at this time. I think Sierra might but they are expensive, some of the rest are round nose, and many really expensive. I looked at the 375 Raptor awhile back, and tbe 45 Rapter. Ended up ordering a 6 5 twist 8.6 barrel & bought a reamer to replace the limited 3 twist. As I have a bunch of 300 gr 338 match that will go both super and sub in the new barrel...to make it more user friendly.
 
I never got around to testing the Sub-X on game, but they shot well on targets.
I few people I knew tried them on small-medium game and had less than stellar results, basically seemed like copper bullets were the only safe bet on game.

If the .375 Speer SPs work well at sub sonic speeds I wonder in their 30cal and 338cals work equally as well?
Not many people seem to use the ol soft point these days so maybe they just haven't been tested as much as the new wizz bang projectiles.
I've shot the Speer 200 gr and 225 gr ...the 200 gr Speer SP held together up until 1600 fps, tested without muzzle devices, in the 3 twist accuracy was okay 3 twist 50 yd type... but the jacket is probably too thick to expand at subsonic speeds, but these bullets can be altered.
A subsonic bullet that expands in the 300 blkout is the 30 cal 85 gr mauser pistol bullet by Hornady, with the point drilled for a hollow point in the lathe, cheap and works for rabbits..but did not cycle the A R action.
 
I'm not saying I disagree but it looks like with 375 Raptor you still run into issues with projectiles like you do with 8.6BLK.

For the most part the projectiles are very similar weight between .338 and .375.
You still are reliant on expensive turned copper bullets.

I can't help but shake the thought to have a true best alrounder for subs and supers you need a cartirdge that'll shoot pistol bullets that'll expand at subsonic velocities.
I shoot 357 mag and 9 mm pistol bullets in a 16" 358 Win AR 10, they are fairly accurate at super sonic speeds and can claim some very high velocities like 3760 fps with 50 gr copper 9 mm bullets from a 16" barrel ...never tried them at subsonic in the AR 10. But they would expand but you'd probably have to work the action for every shot, unless you change a bunch of stuff, then might as well shoot a 9mm pistol in an a AR 15.
 
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I believed there wasn't enough shared data when the 8.6bo came out. For nearly the same weight bullet the 45acp has been around for uber-decades. What is the goal for this cartridge in your hands?
 
I believed there wasn't enough shared data when the 8.6bo came out. For nearly the same weight bullet the 45acp has been around for uber-decades. What is the goal for this cartridge in your hands?

I wouldn’t say it’s the same bullet weight as 45 acp. 45 acp is more aligned with 300blk in terms of weights.

Whether using 8.6 blk, or 338 specter or razorback, the 338 bullets used in subsonic loads can be over 100 grains heavier than heavy 230gr 45 acp, 48% heavier.

Further, you can get much larger expansion in an expanding solid 338. The expanding 338 options act a whole lot more like really fast, spinning broadhead arrows. And finally, you get better sectional density in a 338 subsonic load than 45 acp.
 
Speer doesn't make a 300 gr SP only a 270 gr, & 235gr at this time. I think Sierra might but they are expensive, some of the rest are round nose, and many really expensive. I looked at the 375 Raptor awhile back, and tbe 45 Rapter. Ended up ordering a 6 5 twist 8.6 barrel & bought a reamer to replace the limited 3 twist. As I have a bunch of 300 gr 338 match that will go both super and sub in the new barrel...to make it more user friendly.
sorry, sierra .375 300gr gameking.
I was thinking of previous experiments with the speer 270gr SPBT (which also worked)

The way .375 raptor was designed, according to Arne Brennan himself, is the primary goal was to need minimal changes to the gas system to function in semiauto platforms, as that was considered the primary platform of the cartridge. As long as you're getting a decent gas volume (which tin-star does handily) it will cycle just fine.

worth nothing that mine is a 14.5" P&W job and is pretty much only ever shot suppressed with a Dead Air Primal. I mostly built it for my yearly hog hunting trip to Alabama and for fun. nothing like the match director of a 2-gun asking what you brought to be met with the phrase "my briefcase elephant gun" uses a Cry Havoc QRB system to break down into a few parts with no zero loss. Didn't have to fiddle with the adjustable gas block much to get it running fine. Barrel was made by X-caliber, the rest is pretty standard no-frills AR10 bits. only recent change is the addition of a Stern Rab-AD to pull the stock off and compact the whole assembly down even more, takes about a minute to pull out and assemble maybe faster if you're trying to do it with an eye to speed. Friend of mine calls it the "John Wick Safari Gun"
 
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It seems like its just another brittenham program to copy something that works and screw it up. He and his buddy silvers copied the 30-221 or 300 whisper but changed a few things to make the supersonic loadings less inaccurate but that screwed up the subsonic accuracy. The 300 blackout isn't worth a crap.

Why add the case capacity to a cartridge like the 338 BR which has been around forever and the 338 whisper which JD jones copied from the BR? When you're planning subsonic as the primary use extra capacity is useless. In addition to that the whole superfast twist thing just screws it up more.

I'm sticking with the 338BR which is based on the 30BR or 6.5mm BR necked up to 338. Its a shortened 308 case essentially with a small rifle primer. Running the 300 gr bullets you're looking at about the same powder and charge weight as the 8.6 and the same velocity but with less case overcapacity you're getting a more consistent burn and better accuracy. A twist rate of 1-8 has been standard for years and works great. Going to 1-7 doesn't seem to help or hurt but neither twist rate requires special tooling just to avoid peeling metal off the bore.
The idea that more energy is delivered by spinning things way too fast is crap in real life. It also means you have to put that energy in there in the first place if you really mean to get it out. I believe you're just pushing things past their useful limits.

All in all the 8.6 appears to be the endpoint of a marketing mans ad program. Sell them on the idea and they'll buy the product. Once they've bought it they'll defend it against detractors because they don't want to be seen as idiots. There were already cartridges out there that did the same job and in many if not most cases they do it better. The problem is brittenham wasn't collecting the cash from them....

Just my thoughts based on years of playing with the 338BR and other subbies.

Frank
Agreed. 338 whisper / 338BR is the best of 338 based subsonics and using VV tin star will give you sub moa long range subs.
 
I wouldn’t say it’s the same bullet weight as 45 acp. 45 acp is more aligned with 300blk in terms of weights.

Whether using 8.6 blk, or 338 specter or razorback, the 338 bullets used in subsonic loads can be over 100 grains heavier than heavy 230gr 45 acp, 48%

Further, you can get much larger expansion in an expanding solid 338. The expanding 338 options act a whole lot more like really fast, spinning broadhead arrows. And finally, you get better sectional density in a 338 subsonic load than 45 acp.
You can get a 250 45cal which is in a 33cal. I'm only talking weight wise and are already subbed for 45. How the bullet behaves will be different for sure, but @ 100 yards it isn't making enough difference. Get a 500automax and shoot 600's+ as a true sub without the 8.6 issues. A 3 twist seems ridiculous like others mention.
 
You can get a 250 45cal which is in a 33cal. I'm only talking weight wise and are already subbed for 45. How the bullet behaves will be different for sure, but @ 100 yards it isn't making enough difference. Get a 500automax and shoot 600's+ as a true sub without the 8.6 issues. A 3 twist seems ridiculous like others mention.
Okay, you can get a 250gr 45. And you can get a 340gr 338. The extra 20gr on the 45 doesn’t get it in competition, weight-wise.

Sectional density isn’t just about BC, it’s also about penetration, which is relevant within 100 yards. Then you also have the fact of the expanding 338 solids getting much wider petals than a 45 can mushroom to. More crush damage and more lacerations, weakening the tissue.

Looking at 500 automax, it looks pretty ridiculous and very specialized. The company that makes it uses a custom large frame AR that accepts small frame magazines? And big recoil for a big wide chunk of bullet? Maybe if I wanted to punch through brown bear skulls, but that kind of penetration doesn’t provide any additional benefit in normal hunting situations, or against bipedal threats (if 8.6 blk were ever used in that way). 45 acp and 500 automax are not at all similar in purpose or performance to 8.6 blk, the wildcat 338 subs, or even 375 Raptor.

1:3 twist does have its problems, as shown in this thread. And it is quite possible that the problems outweigh potential benefits in wounding. But that doesn’t mean subsonic expanding solid 338s are synonymous with 45 acp. I bet they are still really great on game with a 1:5 twist (the SAAMI spec), without the issues found in making 1:3.
 
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Okay, you can get a 250gr 45. And you can get a 340gr 338. The extra 20gr on the 45 doesn’t get it in competition, weight-wise.

Sectional density isn’t just about BC, it’s also about penetration, which is relevant within 100 yards. Then you also have the fact of the expanding 338 solids getting much wider petals than a 45 can mushroom to. More crush damage and more lacerations, weakening the tissue.

Looking at 500 automax, it looks pretty ridiculous and very specialized. The company that makes it uses a custom large frame AR that accepts small frame magazines? And big recoil for a big wide chunk of bullet? Maybe if I wanted to punch through brown bear skulls, but that kind of penetration doesn’t provide any additional benefit in normal hunting situations, or against bipedal threats (if 8.6 blk were ever used in that way). 45 acp and 500 automax are not at all similar in purpose or performance to 8.6 blk, the wildcat 338 subs, or even 375 Raptor.

1:3 twist does have its problems, as shown in this thread. And it is quite possible that the problems outweigh potential benefits in wounding. But that doesn’t mean subsonic expanding solid 338s are synonymous with 45 acp. I bet they are still really great on game with a 1:5 twist (the SAAMI spec), without the issues found in making 1:3.
I shoot tmj/fmj's 99% of the time, so expansion is meaningless to me. Whether it be subs in 22's or 50's there will be a right size for someone and bc to go along with it? Don't know why 8.6 is so special unless someone is a metric enthusiast. It's not much different than 338fed or those who went 22creed as a 22-250AI is as close as they'll get. Both will be barrel burners if ant are concerned? 8.6bo is a niche cartridge and there are those who love it. I'm not a sub guy, but do own a 300bo and not for subs. I have a few 185 and 170's that dip into the sub realm because of barrel length. The upper on the automax isn't specialized by any means any more than a 450bm. Just a larger ejection port is all.
 
I shoot tmj/fmj's 99% of the time, so expansion is meaningless to me. ….
Then, there’s not much else to say.
The upper on the automax isn't specialized by any means any more than a 450bm. Just a larger ejection port is all.
The automax uses an AR-10 upper. The 450 BM uses an AR-15. Now, perhaps people use the AR-15 upper with a bigger bolt face for the 500 automax, but the company behind the cartridge chooses to use the AR-10 because of the forces involved.
 
Then, there’s not much else to say.

The automax uses an AR-10 upper. The 450 BM uses an AR-15. Now, perhaps people use the AR-15 upper with a bigger bolt face for the 500 automax, but the company behind the cartridge chooses to use the AR-10 because of the forces involved.
I was just comparing "specialized" uppers is all regardless of platform. I have short mags for AR10's with enlarged ejection port, but not really specialized. All it takes is a Dremel.
 
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For the fun of it I tried shooting a statistically representative grouping with the barrel from Faxon.
I don’t know what people manage to shoot with 8.6BLK @100 meter? There is not much information to find regarding expected precision with 8.6BLK looking at the web. But this group is absolutely useless;
View attachment 8259273
That group’s not going to get many likes on “the gram,” but every one of those hits would kill a hog or deer at that range.
 
My 300BLK with cast projectiles and an ES of like 100fps shot similar to that (about 4" at 100m).

Ok to kill a deer perhaps but still pretty bloody awful.
The older I get, the more I think about the actual task at hand, and less on hypotheticals. In the case of the 8.6, the task is lobbing large projectiles into huge targets (med-large game vitals) at short range. Is 4 moa good? Hell no. Given the task, is it good enough? Yes.
 
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For the fun of it I tried shooting a statistically representative grouping with the barrel from Faxon.
I don’t know what people manage to shoot with 8.6BLK @100 meter? There is not much information to find regarding expected precision with 8.6BLK looking at the web. But this group is absolutely useless;
View attachment 8259273
This group is identical to my experience. I have spent two days at the range trying to zero my 12” Faxon bolt rifle. My groups were so bad, I changed my scope and made sure everything was aligned. I shot 6, 3rd groups. I had a spread between 4-10”. I thought the gun was Crocked I have calls going out to Faxon and gorilla to try and figure what is going on.

I am questioning the 3 twist after reading this thread. I have an AR version with an 3 twist and it shots great. Mostek barrel. My experience with the Faxon setup is different and bad. Should I go with a 3 twist mostek? Or go 5 twist or 6.5 twist like others have suggested. Has anyone shot these other twist rates? Any problems? Or did it fox problems? Thank you!!
 
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This group is identical to my experience. I have spent two days at the range trying to zero my 12” Faxon bolt rifle. My groups were so bad, I changed my scope and made sure everything was aligned. I shot 6, 3rd groups. I had a spread between 4-10”. I thought the gun was Crocked I have calls going out to Faxon and gorilla to try and figure what is going on.

I am questioning the 3 twist after reading this thread. I have an AR version with an 3 twist and it shots great. Mostek barrel. My experience with the Faxon setup is different and bad. Should I go with a 3 twist mostek? Or go 5 twist or 6.5 twist like others have suggested. Has anyone shot these other twist rates? Any problems? Or did it fox problems? Thank you!!
IMO the 3 twist is trouble... part of it appears in the manufacturing, of that tight twist with a button...at least it aint mastered by Faxon, as most complain of. Nothing positive about a 3 twist and an 8 twist will stablize most 338 bullets at sub velocity, as I played with the twist calculator, but went for the 6 5 twist. I have a 6 twist in 223 that preforms well with the heavy bullets, no blow ups or accuracy issues.
I have the same delima with the 8.6 and have ordered a 6.5 Twist 338 blank, I have the reamer but it takes a few months to get the fast twist barrel, to my door.
 
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… Nothing positive about a 3 twist …

Please be intellectually honest. There’s not much positive about it, but there appears to be improved wounding mechanisms with expanding solid copper bullets.

Even if you don’t think it’s true, it’s still a possibility until actually disproven, which hasn’t been done yet.

“I doubt there’s anything positive about a 3 twist” would be a more accurate statement in that case for you.
 
Will the “slower“ twist stabilize a 210 or 225 grain supersonic bullet though? Is there any real world usage or data?
Well “slower” twist barrels stabilize those bullets at supersonic velocities from 338 federal, 338-06, 338 win mag, 340 Weatherby, 338 lapua, among others.

Berger has an on line calculator that will give you the “stability factor” based on the bullet, velocity, and barrel twist.
 
Please be intellectually honest. There’s not much positive about it, but there appears to be improved wounding mechanisms with expanding solid copper bullets.

Even if you don’t think it’s true, it’s still a possibility until actually disproven, which hasn’t been done yet.

“I doubt there’s anything positive about a 3 twist” would be a more accurate statement in that case for you.
The 3 twist ...You like it, you run it... enjoy your 3 twist.
I have it, and don't want it. There must be at least few reasons. I said IMO it holds no value, and that's still true, but has a host of negatives, for my use...and I doubt any animal is gonna die quicker because you used a 3 twist....the bullet turned 4 times instead of two inside the wound cavity, big whoop. Maybe it will clip another blood vessel, maybe it will stop penetration allowing a dangerous animal to kill you.
There is no guarantee of what any bullet will do when striking an animal. They hit bone change direction, tumble, blow up, inadequate penetration for the angle of the shot. I've seen heavy high velocity 338 win mag turn 90° inside a deer, one was a 275 gr went into the chest and came out the top of the back, with two holes in the hide and only one shot...the deer dropped immediately but the bullet performance was off...and it's happened before with a different bullet. Rember all those bullets exiting out the side, top, or bottom,, of the gel, after entering the center...Clear gel test is only so-so and discounted by the FBI for wound cavity vs flesh comparisons ...so there's that.
By into the hype, I do not care, but I'm changing my 3 twist to a 6.5 twist,... been there, tried it, and found it very worst idea and worst barrel, I have ever tried, I knew better... but inquisitive, I had to see for myself. Now I know for sure. It's not for me. You like it, you use it, It felt like covid 19 to me, a real pain in the ass, and hoping I could get over it, without any more injury, to my stuff, as the damage it caused was more expensive than the barrel. A hard lesson taught.
 
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The claims of 1:3 delivering more energy still don’t make a lot of sense to me. A given load of powder has X amount of energy it can impart to the bullet. Any additional energy put into rotation is energy that wasn’t put to forward velocity, and they will offset by probably the exactly identical amount.
 
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The claims of 1:3 delivering more energy still don’t make a lot of sense to me. A given load of powder has X amount of energy it can impart to the bullet. Any additional energy put into rotation is energy that wasn’t put to forward velocity, and they will offset by probably the exactly identical amount.
Theoretically you can add the tiniest bit of extra powder to compensate for the additional “rotational energy” for subs. You don’t need to worry about excessive pressure with subs. But really, the “extra rotational energy” is marketing hype by Brittingham. It’s not actually extra energy on target and he knows it, and has admitted as much. It was just another one of Brittingham’s sleight of hand.

They claim that it helps at farther distances with subs because the energy from the forward movement will quickly be sapped by air resistance, while the rotational energy will not. The rotational energy would stay “constant” (or relatively so) throughout the flight path. However, in reality there just isn’t a whole lot of energy in the rotation, even with a 1:3 twist. The rotational energy is not a big deal. It’s not nothing, but it isn’t anything meaningful.

The only thing that 1:3 twist may get you is better wounding by reducing the elastic limit of tissue through more lacerations and therefore turning more temporary stretch into permanent wound cavities. There needs to be a whole lot more research on that though. I hear that Discreet Ballistics is trying to do some research on game wounds using mobile CT scans, I think.