8.6 Blk reloading info

[45-90]

@45-90 are these numbers with hybrid brass? Could I run these loads in normal brass? Or is there too much pressure?

Today I shot some brass cases in the AR and finished that lot in the bolt gun because of too much pressure in the 3 twist.
The hybrid cases have more H2O capacity by 1 to 1.2 gr, depending on what case the 8.6 has been made from.
And I run them at QL 65,000 psi.
Brass is a bit lower, 58,000 psi area, but will take slightly higher pressures, but not for as long.
Alpha cases are available in 8.6 blk and are good for higher pressure loads also.
Every gun is slightly different and loads must be worked up to.

None of the 6.5 twist high velocity loads are safe in the 3 twist...I just did the experiment on that!
And damaged two cases long before reaching the 6.5 twist velocities!

Absolutely do not use any supersonic data from the 6.5 twist in the 3 twist... Brass or hybrid cases...It will be dangerously way over pressure long before reaching the 6 5 twist velocities.
If you desire that level of performance get a 6.5 twist barrel.
It can not be done with a 3 twist.
I have, as of today, retired my 3 twist forever, as it offers "me" nothing.
It just doesn't have accuracy, velocity, or versatility of the 6.5 twist.
So my whole post is to inform those not satisfied with the Faxon 3 twist, as I have been, in its performance, is to upgrade to the 6.5 twist instead of wasting time and money on tbe 3 twist.

This has been the easy button, almost all my load development is done.
I have it down for most every 338 bullet I'm likely to use, from 160 gr to 350 gr.
Have some 272 gr fmj and 250 SMK to try.

So all the rest of the data will be from the 6.5 twist, not much help for those staying with the 3 twist...also staying with the hybrid cases, they are working out really well, they take more pressure and have slightly more capacity.
The 6.5 twist McGowen has solved all my
8 .6 blackout problems, along with the hybrid cases. It just works with no problems.
If ya stay with the 3 twist you'll have to accept it's limitations, and do your best with what ya have.
These are my experiences with the 8.6, and what I have found out, through a lot of time and expense.
Just sharing the information and trying to keep people on the safe side, while introducing new information, like a different twist rate, that worked for me,... that may or may not be helpful to them...you have more choices.

 

[DRWilson]

Today I shot some brass cases in the AR and finished that lot in the bolt gun because of too much pressure in the 3 twist.
The hybrid cases have more H2O capacity by 1 to 1.2 gr, depending on what case the 8.6 has been made from.
And I run them at QL 65,000 psi.
Brass is a bit lower, 58,000 psi area, but will take slightly higher pressures, but not for as long.
Alpha cases are available in 8.6 blk and are good for higher pressure loads also.
Every gun is slightly different and loads must be worked up to.

None of the 6.5 twist high velocity loads are safe in the 3 twist...I just did the experiment on that!
And damaged two cases long before reaching the 6.5 twist velocities!

Absolutely do not use any supersonic data from the 6.5 twist in the 3 twist... Brass or hybrid cases...It will be dangerously way over pressure long before reaching the 6 5 twist velocities.
If you desire that level of performance get a 6.5 twist barrel.
It can not be done with a 3 twist.
I have, as of today, retired my 3 twist forever, as it offers "me" nothing.
It just doesn't have accuracy, velocity, or versatility of the 6.5 twist.
So my whole post is to inform those not satisfied with the Faxon 3 twist, as I have been, in its performance, is to upgrade to the 6.5 twist instead of wasting time and money on tbe 3 twist.

This has been the easy button, almost all my load development is done.
I have it down for most every 338 bullet I'm likely to use, from 160 gr to 350 gr.
Have some 272 gr fmj and 250 SMK to try.

So all the rest of the data will be from the 6.5 twist, not much help for those staying with the 3 twist...also staying with the hybrid cases, they are working out really well, they take more pressure and have slightly more capacity.
The 6.5 twist McGowen has solved all my
8 .6 blackout problems, along with the hybrid cases. It just works with no problems.
If ya stay with the 3 twist you'll have to accept it's limitations, and do your best with what ya have.
These are my experiences with the 8.6, and what I have found out, through a lot of time and expense.
Just sharing the information and trying to keep people on the safe side, while introducing new information, like a different twist rate, that worked for me,... that may or may not be helpful to them...you have more

Today I shot some brass cases in the AR and finished that lot in the bolt gun because of too much pressure in the 3 twist.
The hybrid cases have more H2O capacity by 1 to 1.2 gr, depending on what case the 8.6 has been made from.
And I run them at QL 65,000 psi.
Brass is a bit lower, 58,000 psi area, but will take slightly higher pressures, but not for as long.
Alpha cases are available in 8.6 blk and are good for higher pressure loads also.
Every gun is slightly different and loads must be worked up to.

None of the 6.5 twist high velocity loads are safe in the 3 twist...I just did the experiment on that!
And damaged two cases long before reaching the 6.5 twist velocities!

Absolutely do not use any supersonic data from the 6.5 twist in the 3 twist... Brass or hybrid cases...It will be dangerously way over pressure long before reaching the 6 5 twist velocities.
If you desire that level of performance get a 6.5 twist barrel.
It can not be done with a 3 twist.
I have, as of today, retired my 3 twist forever, as it offers "me" nothing.
It just doesn't have accuracy, velocity, or versatility of the 6.5 twist.
So my whole post is to inform those not satisfied with the Faxon 3 twist, as I have been, in its performance, is to upgrade to the 6.5 twist instead of wasting time and money on tbe 3 twist.

This has been the easy button, almost all my load development is done.
I have it down for most every 338 bullet I'm likely to use, from 160 gr to 350 gr.
Have some 272 gr fmj and 250 SMK to try.

So all the rest of the data will be from the 6.5 twist, not much help for those staying with the 3 twist...also staying with the hybrid cases, they are working out really well, they take more pressure and have slightly more capacity.
The 6.5 twist McGowen has solved all my
8 .6 blackout problems, along with the hybrid cases. It just works with no problems.
If ya stay with the 3 twist you'll have to accept it's limitations, and do your best with what ya have.
These are my experiences with the 8.6, and what I have found out, through a lot of time and expense.
Just sharing the information and trying to keep people on the safe side, while introducing new information, like a different twist rate, that worked for me,... that may or may not be helpful to them...you have more choices.

Great! My question was in relation to a 6.5 twist. Thank you for doing so much work!!

 

[Mike6158]

For those looking for a 8.6 Blackout shotgun, ....just load up high velocity lead bullets in the Faxon 3 twist AR 10.
Inside, one could shoot down the hall and cover both walls from ceiling to floor.
Loaded on purpose and fun to shoot.

I like my "quiet time" too much but it sounds like you found a portable frag grenade round.

The best group I got with the Faxon garden stake was 3 shots, 0.449", at 100 yards. N133, 19.5gr. Barnes 280gr LRX. ES-7.9, SD-3.3, Avg velocity 1,135fps. I'd hunt with that if I knew the bullet would perform.

Here's a fine powder load test that's barely supersonic. I worked on it in February of this year and it would be closer to subsonic than it was in February. This is N110. 100 yards. I couldn't find a target. Groups size is in inches and measured with a digital caliper. I have other data for faster loads but either the powder burned dirty or the target data was disappointing, or I had become disillusioned with the idea of shooting supers. Still counting down the days until I get my new barrel.

 

[45-90]

Great! My question was in relation to a 6.5 twist. Thank you for doing so much work!!

Yes the hybrid case runs more powder and gets more velocity without pressure signs and retains tight primer pockets. The advantage is for bolt guns only, as you're on the edge of max AR 10 pressures, and could easily exceed it.

 

[wgranvilleb]

Yes the hybrid case runs more powder and gets more velocity without pressure signs and retains tight primer pockets. The advantage is for bolt guns only, as you're on the edge of max AR 10 pressures, and could easily exceed it.

Any suggestions as to where to purchase some hybrid cases?

 

[45-90]

Any suggestions as to where to purchase some hybrid cases?

There are no hybrid 8.6 blackout cases.

They are made from 6.8X 51 military cases, 277 Fury is the civilian name.
Boxed ammo with hybrid cases are sometimes available at $3 or $4 ea for 277 Fury.

So you have to buy the 6.8X51 cases, and trim them, form them, anneal them, FL size them, turn the necks..
Then you have 80,000 psi to play with, in a strong bolt action.

I do not run these at that level in my 8.6 Blackout, but confine them to 65,000 psi.
Where I have a large safety margin, to experiment with any powder available, and still get good velocity and accuracy.

Never used them in 3 twist, as pressures spike is tremendous in those early horrendous Faxon barrels.


I got the best deal at American Reloading, they had thousands at one time but have been out for quite awhile.

Pictured is the process, of making 6.8X51 to 8.6 blackout. Trimmed, Neck turned, and annealed.
Kind of like cheating to the average guy. Yes, I use real machine tools to accomplish these tasks.
Being a retired machinist with machine tools, turns me into a "mad scientist", altering everything, making dies, chambering rifles, truing actions, making AR barrels from blanks, etc.
Few gunsmiths would do these projects, and would be to expensive to pursue.
But, Not if ya do it yourself.
This can be accomplished within hand tools but more time consuming and difficult. For those who want to pursue this endeavor.
Always learning and improving, share what I've learned which may not be useful to many.
Building another rifle today...a 510 Whisper.

 

[wgranvilleb]

Roger that. . . Thanks.

American Reloading had a hundred so I purchased them and will open another arm of this 8.6 reloading process.

I like the idea of the extra safety margin without any intent of pushing beyond regular levels.

Thanks for the guidance regarding the resizing steps. I purchased the Hornady neck turning machine to get started. By the way, when neck turning, how far do you trim into the shoulder?

Regarding reading pressure with these cases. . .

What signs do you rely on for detecting early increased pressure with these steel based cases?
- Is a "stiff bolt" still a sensitive indicator?
- I'm presuming ejector marks are not as reliable.
- Is the shape / condition of the primer the only sign left?
- What is the thinking for pressure correlation when seeing the primer start to flatten but not fully flattened (and not associated with 'stiff bolt lift).

Sorry for so many questions. Many thanks.

 

[45-90]

Roger that. . . Thanks.

American Reloading had a hundred so I purchased them and will open another arm of this 8.6 process.

I like the idea of the extra safety margin without any intent of pushing beyond regular levels.

Thanks for the guidance regarding the resizing steps. I purchased the Hornady neck turning machine to get started. By the way, when neck turning, how far do you trim into the shoulder?

Regarding reading pressure with these cases. . .

What signs do you rely on for detecting early increased pressure with these steel based cases? Is a "stiff bolt" still a sensitive indicator? I'm presuming ejector marks are not as reliable. Is the shape / condition of the primer the only sign left?

What is the thinking for pressure correlation when seeing the primer start to flatten but not fully flattened (and not associated with 'stiff bolt lift).

Sorry for so many questions. Many thanks.

Here is the dangerous part...you could blow up your action before seeing normal pressure signs.
There will be no pressure signs on the case heads at all.
The only clue is primer extrusion, and your into 80,000 psi.
Stiff bolt lift STOP! You're way over proof loads for your action. Your face next to a grenade.

Stiff bolt lift, you just flexed the action, not even damaging the case necessarily, no marks present on the case head, as you pound the bolt open.


But maybe set back the bolt locking lugs. Need to check headspace before continuing....with a much lighter load.

Do not use in an AR 10 at those pressure levels.

It should be done with some scientific predictive software.

And I don't recommend it for a 3 twist.

Should be applied to slower twists maybe 6 twist on down to really slow, like 22 twist.
Cause the bullet doesn't move out of the way fast enough in a 3 twist to create the correct burn and expanding space in the first few milliseconds, for safe predictive operation...that is what I have experienced.

The 3 twist is really limited to subsonic loads, with low pressures, and velocities where it is mostly safe...and was originally designed for, not fast supers, as I have already experimented with, ...you just can not get there with a 3 twist, it's not what it was designed for.

And why I caution extreme care...

 

[45-90]

So here is a photo of two cases
Left 6.5 CM under 80,000 psi, with 147 gr at 2976 fps.
It would destroy a brass case, and maybe your action, but no visible marks on the case head primer is still not really flat...but the primer is flowing a small teat...your only sign... if the action can take tbe pressure.
Right 8.6 blackout at 65,000 psi...not much difference but full primer radius and slight teat forming around firing pin.
There really are no normal clues, no ejector or extractor marks.
I run the 30° tool into the shoulder when neck turning, to thin the shoulder and eliminate donuts in the neck, anneal and resize.
As one can see there is not much difference in high magnum pressure and 80,000 psi hybrid case max running with these cases.
So it's easy to get into trouble. I shoot them in various calibers, and have more than 1500, plus a bunch of experience with these, as an experimenter and shooter.
My cases are carefully machined so as to fit the chamber freely and release the bullet with out any interference.
One can do the same with hand tools but pay very close attention to detail, so as to keep your face...and I would only recommend the lower 65,000 psi area with QL as a guide for anyone trying this.
It's where I'm running my 8.6 and it's good there.

Many powders do not help past the 65,000 to 70,000 psi area... it gets very limited.
The factory uses a classified, special and specific blend for their loads, in military contracts...not available to handloaders.

Sig has lowered the pressure of their factory hybrid loads to 70,000 psi, they are either 7.5 or 8 twist barrels

Got some machining to do, hope this helps....but be very careful.

 

[wgranvilleb]

@45-90:
Fantastic discussion and demonstration of the pressure signs associated with the hybrid cases.
Thank you for taking the time to write this, and the picture is invaluable.
I have no doubt your information will help as they explore this area of loading.

Many thanks . . .

 

[dnchrist]

Thanks for your comment / suggestion.

Yes, they fit after loading.

Not using reformed cases as of yet, as I wanted to decrease the variables during this early phase of load development.

I have dabbled with reforming some .30-'06 cases, most of it is old Lake City brass. The case walls are thick, and after reforming with neck walls that are > ~ .020". Neck turning these reformed cases with the recently purchased Hornady machine is another challenge with its own learning curve, left for a later time.

I've been having good luck with 6.5 Creedmoor Federal SRP, but they require neck turning.

 

[45-90]

I built a die for roughing 30-06, 270, 308, etc to make 8.6 Blackout.
It will form cases with out case lube, as demonstrated here with this crusty old 270 case. But it's better with a light spray of Hornady lube.
They can be done as fast as you can pull the press handle, no shoulder dents or wrinkles.
Then off to the milling machine to cut to length in about one second, from 270, 30-06, or 308.
Full length size, then to the lathe to neck & shoulder turn.
Works good and brass is free...
By hand there is alot of labor involved...
Mechanize where ever you can.

 

[wgranvilleb]

Awesome . . . looks like quite a time saver.
Any interest in selling one to an interested party in the peanut gallery?

 

[45-90]

Awesome . . . looks like quite a time saver.
Any interest in selling one to an interested party in the peanut gallery?

Doesn't hurt to ask, but no.
Too busy doing other things, plus a lot of guys who form brass would want one of these home build dies.
There are none like it, it's one of my inventions. The idea is probably worth a million bucks.
But maybe RCBS will figure it out... in the meantime, guys will have to use factory built forming dies.

 

[wgranvilleb]

Understood. . . Thanks for considering.

Regarding neck / shoulder turning:
- What is your target neck thickness?
- How far into the shoulder do you turn? Do you just relieve at the neck / shoulder junction or turn the shoulder back to the body?

Thanks.

 

[45-90]

Understood. . . Thanks for considering.

Regarding neck / shoulder turning:
- What is your target neck thickness?
- How far into the shoulder do you turn? Do you just relieve at the neck / shoulder junction or turn the shoulder back to the body?

Thanks.

First neck turning should be a combination that leaves close to .002" bullet tension between "your" chamber and "your" die.
With the expander ball doing little work if used.
Mine are. 012" when thick when finished.
And I machine into the shoulder with a 30° on the ground carbide tool, with a smaller than factory radius in the neck shoulder junction.
Pictured sharper than factory radius and fully machined shoulder..
This eliminates neck donuts.
Pictured, Before firing the FL die holds the bullet, after firing the bullet freely slides down the case neck, as pictured.

This is accomplished with a precision lathe and diamond tool grinder.
On thick brass like 30-06 I cut the whole shoulder as much . 008"

Finishing up a 510 Whisper today.

 

[SigSauerM7]

Holy crap.

At 65k PSI, you guys (45-70) are approaching 24 inch 8mm Mauser performance in 16 inch barrels potentially.

Good job!!

225gr at near 2500fps is impressive.

A slicked up Boat tail would be good to 1600yards+

Not bad. Bigger is better.

 

[wgranvilleb]

So I just visited the Maker bullet site for the 350 gr 338 expanding ....thinking of trying a few.
It now says KEEP UNDER 1000 FPS!..
Their ONE load data is 15.9 gr of 296/ H110.
Probably should be running these 900 to 950 fps Max to be safe with the 8.6 3 twist.

@45-90
As a bit of follow-up for this discussion . . .

I called Maker today and spoke with Paul, asking for clarification on the velocity max published on the website for the 350 gr projectiles (1050 fps on one page and 1000 fps on another). In short, Paul's rating is based on a concern for folks loading / testing in a colder climate and shooting in a hotter climate (pushing high-velocity range subsonics over to supersonic levels) and possibly becoming unsafe. However, he says he tests each batch before selling, and is using an 'opening' velocity of 1,130 - 1,150 fps range as 'safe' for general sale. So, loading and testing / shooting in warm weather should be safe at 1,050 fps.

 

[45-90]

@45-90
As a bit of follow-up for this discussion . . .

I called Maker today and spoke with Paul, asking for clarification on the velocity max published on the website for the 350 gr projectiles (1050 fps on one page and 1000 fps on another). In short, Paul's rating is based on a concern for folks loading / testing in a colder climate and shooting in a hotter climate (pushing high-velocity range subsonics over to supersonic levels) and possibly becoming unsafe. However, he says he tests each batch before selling, and is using an 'opening' velocity of 1,130 - 1,150 fps range as 'safe' for general sale. So, loading and testing / shooting in warm weather should be safe at 1,050 fps.

That's nice to know for all the 3 twist guys, and they should heed that advise...barrel length, and temperature change, will make a difference in velocities from these mostly temperature sensitive powders used.
I again, do not have to worry about it with the 6.5 twist, I ran them to almost 1700 fps, with excellent accuracy.
Finished loading for the 510 Whisper, I finally got around to building...tomorrow is .510 day.

 

[swandme]

No, if kept subsonic, the 300 gr Berger and 300 SMK were the most accurate in my 16" barrel...keep 285 ELDM below 1400 fps ...at 1400fps they did not make it to the 50 yd target.
Shoot without a muzzle device as they blow up as soon as they leave the confines of the barrel and destroy the muzzle device and the magneto speed bayonet.
My two best loads are 300 gr Berger 15.8 gr imr 4189 very consistent, and 300 gr SMK 15.8 gr Accurate 1680 are both accurate. And just about the only ones worth considering as this is a subsonic caliber, with too much capacity for subs and too little for high velocity. Plus lighter lead bullets blow up and copper too slow be of any use and inaccurate in the 3 twist. IMO...the 8 6 Blackout is a fun expensive 300 gr 338 Sub plinker.

Just checking if I read this wrong

Is it 4189 or 4198

Thanks for sharing the info

 

[swandme]

That's nice to know for all the 3 twist guys, and they should heed that advise...barrel length, and temperature change, will make a difference in velocities from these mostly temperature sensitive powders used.
I again, do not have to worry about it with the 6.5 twist, I ran them to almost 1700 fps, with excellent accuracy.
Finished loading for the 510 Whisper, I finally got around to building...tomorrow is .510 day.

We call our 511 short

690 ball sub or up 1620

It’s a hoot

 

[45-90]

Just checking if I read this wrong

Is it 4189 or 4198

Thanks for sharing the info

Nope, I typed it wrong...imr 4198 is correct. Thanks.

 

[DRWilson]

Because hybrid brass is hard to source, it will be about modifying @45-90 data for his 6.5 twist loads on regular brass. I’ll begin mine in early fall on regular brass. Has anyone started adjusting his loads development to support lower pressure cases? Thx!!

 

[45-90]

Because hybrid brass is hard to source, it will be about modifying @45-90 data for his 6.5 twist loads on regular brass. I’ll begin mine in early fall on regular brass. Has anyone started adjusting his loads development to support lower pressure cases? Thx!!

I would suggest getting Alpha Munitions 8.6 blackout brass, if one can not find hybrid brass cases.
It handles high pressures better than "regular" factory brass.
I've seen it $118 per hundred free shipping, but it's usually around $125 per hundred.
Plus no neck turning, or case forming.
I was going to order some, and try it, but am into the 510 Whisper loading at this time...it brings a crazy variety of loads with lots of power.
Example is the 1002 gr 1.175 BC bullet that starts out at 1100 fps sub load with a muzzle energu of 2700 ft/lbs and gets to 1000yds with 2000 ft/ lbs of energy!

Remember I did the test on the 3 twist vs the 6.5 twist and pressure signs show up heavy on the brass cases like 3 grains sooner with the 3 twist barrels on supers...in my rifles, ..note the Faxon 3 twist has very poor rifling, when new, it was torn, pitted, and galled...for that reason alone printing 6.5 twist data isn't all that helpful for horribly rifled 3 twist...unless one works up slowly...depending on how their rifling turned out, especially in early barrels.
Plus the 350 Maker can be ran as fast as one can shoot it in the 6.5 twist without fear of damaging the muzzle devices.
Always remove muzzle devices when testing new bullets and all high velocity loads.
Pushing the 350 Maker close to 1700 fps in this ladder test in the 6.5 twist with good accuracy, no bullet failures. This could be done in any 6.5 twist and Alpha Munitions cases...as I can add another 10 to 15 thousand psi to this load with machined hybrid cases...but I do not find it necessary to do that at this time, for another 100 fps, or so.