8.6 Blk reloading info

[MSBRPT]

Has anyone tried subsonic in the slower 1:6 twist barrels? If so, did it yield better accuracy than the 1:3?

 

[45-90]

Has anyone tried subsonic in the slower 1:6 twist barrels? If so, did it yield better accuracy than the 1:3?

I have some loaded as well as supers, for my 6.5 twist.
But came down with a bad case of shingles, so it will be awhile before I return to test them.
I did shoot ladder test with super sonic and the 6.5 twist was much more accurate than the 3 twist, before getting sick. In fact some excellent super groups.
But, that may not be a fair comparison.
The 3 twist is a Faxon barrel with its inferior torn rifling...and the 6.5 Twist is a custom ordered barrel took 3 months to get, as a barrel blank...that needed to be chambered and threaded, it has a nice interior.
I see no need for the radical 3 twist, and I own one,...and that was enough.

 

[Mike6158]

Faxon was the only game in town when I bought my barrel. In simple terms, it's a pile of crap. I don't think I'd trust it for a tent stake. The "torn rifling", drilling the gas port through edge of a land and groove, and the extremely small diameter of the barrel make the Faxon barrel no more than better than slightly better than nothing. .720 at the skinniest and longest points only leaves .194 wall thickness after subtracting the bullet diameter. Divide by two to get wall thickness. It's no wonder the accuracy is so poor. 1/2 of the barrel length is thin and that's split on either side of the gas block. It's no wonder the thing slings bullets all over the target.

Sorry to hear about the shingles 45-90. So far I've not had those but I hear it's pretty rough. I think the cartridge has good potential. I'm seriously considering going with an aftermarket heavy barrel. I'm not sure which twist and that's only because 45-90 is testing the 6.5 twist in a rifle. I don't own an SBR but I'm toying with the idea of trying a heavy, short barrel in 3 twist. Then again... why not do the same thing in 6.5 twist? Idk... It'll be subs only if I try it.

Speaking of of 45-90, I really want a 45-90 from Shiloh Sharps. Not bad enough to order one just yet . I think I'll get an off the shelf .45-70 and shoot that first. I have all of the dies, a box of full of .45-90 brass, bullet molds, etc. Just what I need... something else that goes bang.

 

[45-90]

Get the 45-90...life is too short. You have the stuff....so fulfill the dream.
Its shoots 500 gr cast and 350 gr Berrys heavy plated rated at 1900 fps. subsonic or super your choice.
I use 45-70 and 45-90 brass. Some 45-70 for subs.
I use the lathe & collets to drill deep hollow points in Berrys bullets .200 deep hp 10.3 gr of Red Dot for 864 fps, quiet small game load, little recoil. Or 10.5 red dot 250" deep hp for 1113 fps. 10.3 red dot on a 350 gr no hollow point 952 fps.
Or have cast 500 gr subs for heavy game or Hornady Sub X 410 gr super or sub.
Recoil gets stout when 500 grs are 1800 fps or over, but always fun to shoot a few.

Before I got sick a few weeks ago I fired 100 rds of 45-90, without stopping, the barrel was so hot I had to hold low on the walnut stock to escape the heat from burning my fingers...and let the barrel cool 15 minutes before putting in the gun case and head home...my other rifle was the 8.6 blackout 6.5 twist, out for testing...

 

[Stangman46]

Thank you, sir. I wish I would have done some research before I bought the brass. All of the rounds I have loaded pass the gauge test and slide all the way in and out. The Hornaday turning too has a cutter with the same angle as the shoulder taper. I am going to try bumping the necks a bit, and then checking the durability of them before loading. If that doesn't help, I am going to send the barrel back and have them look at it.

So after letting this sit for a while, I decided to pick it back up again. Thanks to all that lent their expertise. I did end up getting down into the transition below the neck a bit. That made the loads fit the gauge even better. It also made them fit in my rifle and fire correctly. I made a collet to fit my lathe to make the process faster. Thank you 45-90 for your post on that. I worked up a couple different loads for testing. After figuring out my Cauldwell chrono was junk, I picked up a Garmin Zero C1 Pro. This thing is fantastic and easy to use. Here is what I came up with and the results.
Both these loads are with Hornaday 285 ELD-M bullets, CCI 200 primers, and mixed brass. COAL 2.76 on both loads. The groups were decent. Sorry no pictures. I am working on some loads with Hornaday 270 ELD-X bullets. Will report my results when I test.

1st test round 16gn A-1680:
1. 1010.3
2. 1028.2
3. 1052.0
4. 1049.1
5. 1040.2

2nd test round 17gn A-1680
1. 1097.8
2. 1093.5
3. 1115.1
4. 1083.6
5. 1083.2

 

[Huckleberry75]

Get the 45-90...life is too short. You have the stuff....so fulfill the dream.
Its shoots 500 gr cast and 350 gr Berrys heavy plated rated at 1900 fps. subsonic or super your choice.
I use 45-70 and 45-90 brass. Some 45-70 for subs.
I use the lathe & collets to drill deep hollow points in Berrys bullets .200 deep hp 10.3 gr of Red Dot for 864 fps, quiet small game load, little recoil. Or 10.5 red dot 250" deep hp for 1113 fps. 10.3 red dot on a 350 gr no hollow point 952 fps.
Or have cast 500 gr subs for heavy game or Hornady Sub X 410 gr super or sub.
Recoil gets stout when 500 grs are 1800 fps or over, but always fun to shoot a few.

Before I got sick a few weeks ago I fired 100 rds of 45-90, without stopping, the barrel was so hot I had to hold low on the walnut stock to escape the heat from burning my fingers...and let the barrel cool 15 minutes before putting in the gun case and head home...my other rifle was the 8.6 blackout 6.5 twist, out for testing...

Not to derail the thread, but an '86 in 45-90 is a bucket list rifle for me, and the short list at that.

 

[45-90]

Not to derail the thread, but an '86 in 45-90 is a bucket list rifle for me, and the short list at that.

Yep, gotta have an Win 1886 short rifle in 45-90 ...and Real SAA in 45 Colt caliber, made by Colt. A fun way to hit the mountain trails.

 

[Huckleberry75]

.45 colt = the Lord's caliber

 

[Mike6158]

I shot my N133 subsonic test today (03/13/24 since I forgot to date the spreadsheet). It was windy but the wind was from the south and I shot to the north. The pistol berms and trees around the range do a good job of blocking / lifting the wind to some degree. Aero Precision M5 upper and lower, Superlative Arms gas block, Geissele trigger, 12" Faxon round thing with rips and tears on the inside, and that's being nice. I shot the test with my Dead Air Primal installed.

Group size is below ES/SD on the Excel sheet. Group 1 and 2 had acceptable 100 yard groups sizes. 2 was real nice. I could have done better with a slingshot for the other 7 groups. I really think it's the barrel. I guess we'll see when I get the new barrel. Have I mention the barrel enough?

The Garmin didn't record 3 shots, which is annoying. It also negates two of the groups (4 and 7). Since they are lower velocity than where I want the round to be I'll get over it (I really won't). I'm still learning how to set it up so that's probably on me. I had some good ES values that, other than the first string, didn't produce good groups.

I didn't get to 1,100 - 1,110fps with this test. That was the goal. I expected to pass into low supersonic range and didn't get there. There were no pressure signs. I'll explore higher, probably 18.4 to 18.9. There were some decent ES's. There's big, fat node right in the middle but no groups to back it up. Again, I think a huge component of that is the barrel. We'll see.

This looks like a good alternative powder for subs. With any luck I'll get to test the bullet at subsonic velocities on a pig Friday or Saturday. If it doesn't do well I'll move on to something else for subs.

 

[MSBRPT]

I shot my N133 subsonic test today (03/13/24 since I forgot to date the spreadsheet). It was windy but the wind was from the south and I shot to the north. The pistol berms and trees around the range do a good job of blocking / lifting the wind to some degree. Aero Precision M5 upper and lower, Superlative Arms gas block, Geissele trigger, 12" Faxon round thing with rips and tears on the inside, and that's being nice. I shot the test with my Dead Air Primal installed.

Group size is below ES/SD on the Excel sheet. Group 1 and 2 had acceptable 100 yard groups sizes. 2 was real nice. I could have done better with a slingshot for the other 7 groups. I really think it's the barrel. I guess we'll see when I get the new barrel. Have I mention the barrel enough?

The Garmin didn't record 3 shots, which is annoying. It also negates two of the groups (4 and 7). Since they are lower velocity than where I want the round to be I'll get over it (I really won't). I'm still learning how to set it up so that's probably on me. I had some good ES values that, other than the first string, didn't produce good groups.

I didn't get to 1,100 - 1,110fps with this test. That was the goal. I expected to pass into low supersonic range and didn't get there. There were no pressure signs. I'll explore higher, probably 18.4 to 18.9. There were some decent ES's. There's big, fat node right in the middle but no groups to back it up. Again, I think a huge component of that is the barrel. We'll see.

This looks like a good alternative powder for subs. With any luck I'll get to test the bullet at subsonic velocities on a pig Friday or Saturday. If it doesn't do well I'll move on to something else for subs.


View attachment 8371959

It’d be nice if #2 turns out to be consistent. I looked over my older notes and found that my consistent loads all used SRP brass. I’m going to try going back to SRP until I find LRP brass loads that work.

 

[45-90]

Gotta keep trying, the SR primered cases may help...along with powders that give good fill, by volume.
Much of the accuracy problems are in the Faxon barrels, and a quality barrel replacement is the answer for better accuracy with a slower twist.
But, they should be accurate enough for short range.
Shot some 300 Bergers at 2 liter jugs...they were very unimpressive as to killing power.
Even at 1943 fps they just punched a .33" hole on the 2 liter...like shooting it with a Bow using a point target arrow...the liquid slowly drained out.
200 gr lead at 2480 fps exploded the 2 liter in the 6.5 twist.
I'm going for the highest velocities instead of subs this go round...using mostly lead bullets without worry of them exploding in the muzzle brake, with the 6.5 twist.
Will shoot a few subs also.
The 300 gr Bergers are for long range target, only, IMO.
They just punch a small caliber hole even way above sub speeds...look like they would be slow kills, even on squirrels.
Recovering from being sick...will be back out testing the high velocity loads in a few days.

 

[Mike6158]

It’d be nice if #2 turns out to be consistent. I looked over my older notes and found that my consistent loads all used SRP brass. I’m going to try going back to SRP until I find LRP brass loads that work.

I've got 10 loaded. I hope to do a hog test on Friday or Saturday. I think I'll load 10 more and see what a 10 shot group, at a 100, looks like. I just looked, every case I have is large rifle pockets. I've reloaded a lot of the early Gorilla case 1 or 2 times, no more than that, and the primer pockets get sloppy. .

Gotta keep trying, the SR primered cases may help...along with powders that give good fill, by volume.
Much of the accuracy problems are in the Faxon barrels, and a quality barrel replacement is the answer for better accuracy with a slower twist.
But, they should be accurate enough for short range.
Shot some 300 Bergers at 2 liter jugs...they were very unimpressive as to killing power.
Even at 1943 fps they just punched a .33" hole on the 2 liter...like shooting it with a Bow using a point target arrow...the liquid slowly drained out.
200 gr lead at 2480 fps exploded the 2 liter in the 6.5 twist.
I'm going for the highest velocities instead of subs this go round...using mostly lead bullets without worry of them exploding in the muzzle brake, with the 6.5 twist.
Will shoot a few subs also.
The 300 gr Bergers are for long range target, only, IMO.
They just punch a small caliber hole even way above sub speeds...look like they would be slow kills, even on squirrels.
Recovering from being sick...will be back out testing the high velocity loads in a few days.

The 280 gr Barnes LRX bullet is seated so far into the case that it is close to if not touching the top of the upper end of the N133 powder charges that I used. I'll try to remember to a better approximation when I load the retest I mentioned above. I hope it performs well at short range, subsonic velocities. 50 - 100 yards would be perfect. I'm not optimistic lol but I'm enjoying the hunt for a good load, not counting the Faxon issues. I am looking forward to trying the new barrel. If it works I may talk myself into a 16" barrel from them and revisit supers in the AR. It'll be a long wait...

I'm glad to hear that you're recovering.

 

[Mike6158]

I was supposed go fly this morning but the weather is not the best today. I went full on "science" and measured case fill for the 17.6gr N133 charge. I'll check it when I load the larger charges in a bit. I hit post after I've done some checking.

It’d be nice if #2 turns out to be consistent.

I used a "SAMMI spec" wooden dowel that fits into the neck of the case. I slipped it into the case, marked the end of the neck, removed the dowel, loaded a charge, lightly inserted the dowel, measured to the mark, did some cyphering.

Caveat: I'm listing 3 decimal places. I'm sure everyone understands that I'm eyeballing the calipers as best I can so 3 decimal places may or may not be accurate. So this one of those "it's about right here" measurements not a NIST standard measurement. I might be within .005". Might not.

Empty case to neck: 1.467"
Approximate distance to the base of the shoulder. Ie the fat part of the case: 1.062"
Distance from the neck to the top of the 17.6gr charge: 0.655"
% case fill (fat part of the case, not shoulder): precisely approximately 61.67%

Distance from the neck to the top of the 18.9gr charge: 0.666" (mark of the beast?)
% case fill (fat part of the case): precisely approximately 62.71%

Bullet base to tip: 1.858"
Bullet loaded with a CBTO of 1.940 tip to top of the neck: 1.162"
Estimated insertion depth of the bullet, neck to base: 0.696"
That puts the bullet at 0.041" from the top of the charge.

I decided to check the 18.9gr max charge that I selected:
18.9gr charge is .030" from the base of the bullet.

It seems like I have room to go with N133 for subs. I don't think I'll need it.

 

[SkyScrapin]

@Mike6158 Have you tested CFE BLK yet? I saw it was next

 

[Mike6158]

@Mike6158 Have you tested CFE BLK yet? I saw it was next

I haven't but I've got the time and brass to load some today. I really need to see if the 280gr LRX will perform with subs before I get too excited about loading it. If I can find a good ES that groups with CFE Black that might be useful. I'm not optimistic about finding "groups" with the barrels I have. I have the one 0.682" group that I need retest just to see if it repeats. I hope to find another N133 node at higher velocity (but still subsonic).

 

[Mike6158]

Onward thru the fog. I had a short weather window so I sacked everything up and made the 45m trek to the range to shoot out what I thought was the final supersonic test. It's not. You see... the speed of sound changes with air temperature. A table of values would look something like this (it was 85 degrees today):

Deg F ft/s
50 1,706.42
60 1,117.22
70 1,127.92
80 1,138.52
85 1,143.78
90 1,149.02
100 1,159.43

Shot data table below. The load for the .6 MOA group from the previous test is in column 10.

It was windy... like annoying 25kt and gusty, quartering right to left tailwind. There was no escaping it. I only whine about that because the group for column 10 would have been as good as the first go around with 5 shots. The wind just spread it out right to left. Less than an MOA of vertical. The 3 shot test load ES was 17.5. Five shots was 18.1. Not terrible. Every string was quiet. I shot through the Dead Air Primal again.

When I got there two guys had their sh*t spread out over 7 or 8 benches and a blob of targets scattered everywhere. They must be new. Most people have better behavior than that. So, I went to the far left side of the 100 yard range and put up one target. I shot the test into different segments of that target. I kept up with the group in #10 and a few of the others. Group #4 was .912. The others were close to MOA. Considering the wind, these are good groups. The two crappy groups, like 1.5" or greater, were #2 and #3. You can see that in the ES. N133 is a good powder for subs imho. Maybe supers too.

I'm going to use group 4 as a cool weather load and see if I can get to 1,150 / 1,160 fps for warm hot weather. I don't think I'll have any issues getting to 1,160 fps.

 

[45-90]

Well got the super sonic test done today for the 8.6 Blackout with a 6.5 twist.
Top velocity for the cheap Speer 200 gr lead bullets was 2604 fps with H335.
AA 2495 =2451 fps
CFE223= 2572 fps
IMR 4198 =2433 fps
2000 MR =2494 fps 4.3 S/D

Machined copper Hornady 225 gr GMX cut down in lathe collet to 154 gr were fired with H335 and reached 2788 fps.
Caught one in water jugs it mushroomed up very nicely.

Shot a few 300 gr Subs in both Sierra with 1680 and 300 gr Berger with imr 4198 in the 6.5 twist the Sierra strung out vertically...the Berger was round 5 into 1.1"
All in all a successful day. The 6.5 twist is totally versatile as I suspected it would be. And the 8.6 Blackout comes close to the 338 Fredral, with supers, for some real killing power.
There was snow still heavy on the road and fallen trees across the road. Had to turn back to a bit lower elevation.

 

[AlphaMikeBravo]

Using Reloaded 15 with subsonic 300gr pills.

Has anyone tried RL 15 with 300gr subs out of an 8inch barrel? Using gordons reloading tool it looks promising. My goal is to try and get a higher fill volume in the case primarily so overthrows are more noticeable. With Accurate 1680 an overthrow is very easy (dont ask me how I know).

Basically looking for any powder that can get me north of 65% case fill that will work well with subsonic 8.6blk reloads.

I would appreciate any feedback.

Regards

 

[Mike6158]

^^ Post #715 and #719. Depending on the temperature, N133 might get to 65%. 18.9gr of N133 is about 62.7%. That averaged about 1,134fps.

The next round of testing starts at 19.0gr. I'm looking for subsonic at 90 - 100 deg F, 1,149 to 1,159. 90 to 95 is a TX Gulf Coast summer.

The next test starts at 19.0gr and ends at 19.5gr of N133. 19.5gr is about 65.44% case fill. That's the fat part of the case not into the shoulder. <edit> I'm going to add 19.6g to the test.

My barrel is 12" though...

Speed of sound at x deg F
Deg F ft/s
50 1,706.42
60 1,117.22
70 1,127.92
80 1,138.52
85 1,143.78
90 1,149.02
100 1,159.43

 

[Mike6158]

i just did a backyard test, 1 round each, on 19.6g, 19.7g. and 19.8g of N133. 78 degrees. Speed of sound is 1,136-ish fps. There was a definite crack for all three rounds.

19.6g N133 1,143.3 fps
19.7g N133 1,150.6 fps <-- this is possibly the hot summer day load.
19.8g N133 1,166.3 fps

 

[Mike6158]

Using Reloaded 15 with subsonic 300gr pills.

Has anyone tried RL 15 with 300gr subs out of an 8inch barrel? Using gordons reloading tool it looks promising. My goal is to try and get a higher fill volume in the case primarily so overthrows are more noticeable. With Accurate 1680 an overthrow is very easy (dont ask me how I know).

Basically looking for any powder that can get me north of 65% case fill that will work well with subsonic 8.6blk reloads.

I would appreciate any feedback.

Regards

Looking at the burn rate chart:

CFE Blk is fastest (74)
N130 is slower (84)
N133 is a little slower (89)

The trouble with the burn rate chart is that it's not linear. If you're looking for case fill N133 might get you where you want to go.

 

[45-90]

I have been working on super sonic loads with only a little on Subs with the AR platform 3 twist Faxon mostly a disappointment.
I chambered a bolt gun, trued the 700 action, and installed a 24" 6.5 twist. So supersonic is fast, tried a few left over 300 gr subs one load of imr 4198 showed better accuracy, then AA1680, which had vertical stringing and high S/D s.
I have used Trailboss in 308 & 50BMG sub loads, but do not have much left.
Another guy used Tin Star for his 8.6 build but both of these bulky powders are unavailable.
Getting the velocity SD low as possible are key if ya want to extend the range of the subsonic 8.6 loads. Close range hunting at big game it's not as important.
May try some Trail Boss in the 6.5 twist out of curiosity. Also could change to SR cases or use pistol primers to get S/D down, on sub loads. Lots of experimenting to do.

 

[Mike6158]

I've got most of a jug of Trail Boss. I never thought about loading 8.6 with that. I used to load .308 subs with it. I may have loaded 100 rounds out of the jug. That was way back when life was simple and I didn't think I needed to reload every freaking caliber made. Well not all of them, just the oddball calibers. I like N133. It's clean and it's given me some good ES values.

 

[45-90]

I've been looking at it seriously tonight.
You want high bulk density and 100% burn a tough combination with this case capacity.
10.2 gr of Trail Boss on a 300 gr Sierra MK bullet at abiut 2.760" to 2.8" should work.
Have to play with the charge to get the velocity.
Also Clay's is bulky and 100% burned about 10.0 gr for the same 300 gr bullet, not as good bulk wise as Trail Boss, though.
Get too slow of a propellant to fill up the case..but not all the powder is burned, usually causing velocity variations.
With a good barrel one should find something acceptable....at least able to satisfy your needs for the cartridge.
These are for bolt guns, my not produce enough gas to operate a gas gun.

 

[45-90]

Installed a more expensive scope on the 8.6 to help me see the target.
Shot the subs today to see how they do in the 6.5 Twist McGowen barrel, I chambered and installed on a trued Remington 700 which I also did in my shop.
Snow still on the ground and fallen trees everywhere, but I made it out to shoot .

Tried some Trail Boss and Red Dot, with LR and LP primers, to see the result.
With Red Dot there was little difference in velocity, but better accuracy and better S/D with the LR primers.
But Trail Boss was shocking... about 250 fos difference, 741fps to 482 fps LR vs LP primer...had to stop the test to make sure the bullet exited the barrel, it did but that velocity is too low to continue with the pistol primers.
The remaining 4 Trail Boss loads st 700 fps went into about .8" low off the plate into the cardboard backer, but this is not the powder, S/D too high, even though the load density is great. The 6.5 twist stabilized the 300 SMK at 700 fps. Plus cheap 200 gr Speer lead bullets to 2600 fps.
Much more versatile than my inaccurate Faxon 3 twist, which would limit lead bullets to about 1200 fps as they came apart if shot much faster.
Red Dot had a good showing lower S/D and 5 shot groups hit .4"
Had AR 10 loads, already loaded 300 gr Sierra MK with AA1680 15.8 gr. S/ D was a bit high but it put 8 shots into .5" with the 6.5 twist bolt gun, the AR 10 Faxon 3 twist was about 2" plus for 5 shots, and this was its best load for the 300 gr SMK.
A good day out shooting.

 

[Mike6158]

I'm on the road this evening so I don't have my load data with me. I was supposed to put it in the pickup before I left but that didn't happen for some reason. It was 30 degrees cooler today than the last time I shot. 53 deg. F. The load sequence was just a continuation of that prior load test. The initial velocity today was lower than the the highest velocity from the previous test. It could be that the powder is more temperature sensitive than I thought. I need to keep and eye on that. I did manage to get to the same velocity as I got in the backyard test a few posts up. Lots of variables are still not nailed down.

I might shoot it again when it's warmer but I think I'll wait for the new barrel to test more. I feel like N133 is going to work for me. I bought N133 to use in my .20PPC. Those loads are really nice. 1/4" or less 200 yard groups. 200 yards is far enough that I hold the same aim point and don't see what the groups size is until I pull the target.

I still need to see what terminal ballistics look like before I commit to the Barnes LRX (more than I already have).

 

[SkyScrapin]

I’ve got a pile of Maker 350gr bullets and Hornady CX. Hoping CFEBLK works okay in both.

 

[45-90]

Noticed some new Alpha Munitions 8.6 Blackout cases, called OCD, as they optimized for high pressure and have SR primers. Available at Mile High Shooters for $125 per hundred.
They should give you a one extra protection with your normal loads....but allow for a bit extra performance with out going overboard.
The 308 OCD cases were taken to 100,000 psi in a Bat action in a test, video on Ultimate Reloader, Do not do this at home , 308 Win completing with the 300 WM. Titled show.
For those interested....check it out...I may try the Alpha 8.6 OCD brass myself, later.

 

[tom12.7]

Pretty sure the Alpha OCD 8.6 brass I picked up is LRP.

 

[MSBRPT]

Noticed some new Alpha Munitions 8.6 Blackout cases, called OCD, as they optimized for high pressure and have SR primers. Available at Mile High Shooters for $125 per hundred.
They should give you a one extra protection with your normal loads....but allow for a bit extra performance with out going overboard.
The 308 OCD cases were taken to 100,000 psi in a Bat action in a test, video on Ultimate Reloader, Do not do this at home , 308 Win completing with the 300 WM. Titled show.
For those interested....check it out...I may try the Alpha 8.6 OCD brass myself, later.

I saw on Alpha’s site that they offered 8.6 brass only in LRP. I wonder if the SRP on Mile High is a typo.

 

[tom12.7]

Bet it is a typo, the pic on Mile High shows LRP.

 

[45-90]

Bet it is a typo, the pic on Mile High shows LRP.

Could be a typo, on the SR priner pocket.
I was intrigued, at the add, and thought I'd share for those who might want to give that a try in their subs.

 

[45-90]

Since I'm running a 6.5 twist,...now... been doing alot of high velocity testing, got a bunch of bullets coming to test. Getting good sub groups already with 300 gr match bullets. Don't plan on hunting with the 8.6 in that capacity. I running reformed .277 Fury hybrid cases almost exclusively in the 8.6 Blackout finishing another 100.

 

[Floridapanhandle]

Just finished building my 8.6. 12" Faxon 1-3 twist barrel. Porq chop suppressor . Gorilla case, Remington large rifle primer, 14.7 gr Accurate 1680, bullets are 300 grain seconds that came from Midway. Pretty sure they are Sierra Match King. 934 ft sec average. Bolt cycles and locks on last open on last round. Going to go up a few grains and see if I can get between 1025 - 1050 ft sec.

 

[fortify503]

Just finished building my 8.6. 12" Faxon 1-3 twist barrel. Porq chop suppressor . Gorilla case, Remington large rifle primer, 14.7 gr Accurate 1680, bullets are 300 grain seconds that came from Midway. Pretty sure they are Sierra Match King. 934 ft sec average. Bolt cycles and locks on last open on last round. Going to go up a few grains and see if I can get between 1025 - 1050 ft sec.

OAL?

BTW - I've been warned about increasing by "grain" amounts and ushered to only increase loads by fractions of grains due to how quick pressures spike in this particular case.

if you're looking to achieve ~10% velocity increase I was advised into .5gr max. increment increases (not sure if that applies to subs and supers or just one of those)

 

[Mike6158]

Alpha brass is first class stuff. It's shipped in a 100 count case. A nice one. The necks aren't all banged up and the brass is very consistent. Much better than Q or some of the other sources. I'm not going to load any of it until the new barrel comes in.

 

[Mike6158]

OAL?

BTW - I've been warned about increasing by "grain" amounts and ushered to only increase loads by fractions of grains due to how quick pressures spike in this particular case.

if you're looking to achieve ~10% velocity increase I was advised into .5gr max. increment increases (not sure if that applies to subs and supers or just one of those)

An F Class shooter gave me the following advice:

Powder Charge
<30gr: 0.1gr steps / Fine Powder: 0.05gr steps
<= 60gr: 0.2gr steps / Fine Powder: 0.1gr steps
60-100gr: 0.5gr steps / Fine Powder: 0.25gr steps
>= 100gr: 1gr steps / Fine Powder: 0.5gr steps

Seating Depth
Best: (Amp Press and SAC Infinity die): 0.001”
Better: 0.002”
Good: 0.003” (Hunting or non-precision target shooting)

It makes sense from a % of fill / % charge change perspective. Fine powder doesn't mean how course the powder is. It means the increment of the next step in a powder charge test.

 

[45-90]

Alpha brass is first class stuff. It's shipped in a 100 count case. A nice one. The necks aren't all banged up and the brass is very consistent. Much better than Q or some of the other sources. I'm not going to load any of it until the new barrel comes in.

I looked at the Alpha brass in 8.6 blackout and considered getting some because its good brass, I use it in 6 Dasher

It will handle high pressures, probably not needed in most subs, but good consistency might help with vertical on the longer range targets, with lower extreme velocity variations.
I'm doing good with the 6.5 twist with 300 gr subs, with hybrid csses, but wonder if Alpha brass could make that even better.
So I'm gonna order some. It's been selling fast as some were $118 per hundred. Look for free shipping, promo codes.

After using the 6.5 twist and getting almost 338 Federal velocities with cheap lead bullets and over 3000 ft/ lbs of energy, plus excellent accuracy from the sub 300 gr loads, I'll probably never use my 3 twist barrel again, as it's so limiting and does not provide the accuracy of the 6.5 twist barrel.
Got a bunch of High velocity bullets coming for hunting Barns 160 gr to 250 gr to see what velocities are possible with the 8.6 blackout.

Plan to turn the old 3 twist 8.6 blackout AR 10 into an AR 10 338 RCM 18". Ordered the chamber reamer, gauges, barrel, have the modified bolt and upper, with dies, and brass to modify on the way. It always takes a few months to acquire all the stuff.

 

[MSBRPT]

I looked at the Alpha brass in 8.6 blackout and considered getting some because its good brass, I use it in 6 Dasher

It will handle high pressures, probably not needed in most subs, but good consistency might help with vertical on the longer range targets, with lower extreme velocity variations.
I'm doing good with the 6.5 twist with 300 gr subs, with hybrid csses, but wonder if Alpha brass could make that even better.
So I'm gonna order some. It's been selling fast as some were $118 per hundred. Look for free shipping, promo codes.

After using the 6.5 twist and getting almost 338 Federal velocities with cheap lead bullets and over 3000 ft/ lbs of energy, plus excellent accuracy from the sub 300 gr loads, I'll probably never use my 3 twist barrel again, as it's so limiting and does not provide the accuracy of the 6.5 twist barrel.
Got a bunch of High velocity bullets coming for hunting Barns 160 gr to 250 gr to see what velocities are possible with the 8.6 blackout.

Plan to turn the old 3 twist 8.6 blackout AR 10 into an AR 10 338 RCM 18". Ordered the chamber reamer, gauges, barrel, have the modified bolt and upper, with dies, and brass to modify on the way. It always takes a few months to acquire all the stuff.

I went with the 6 GT SRP brass. Couldn’t get enough data to come to any conclusion. I loaded 9 cartridges using CCI BR4’s and had 5 failure to ignites. It was definitely easier sizing up without having to neck turn.

 

[45-90]

I went with the 6 GT SRP brass. Couldn’t get enough data to come to any conclusion. I loaded 9 cartridges using CCI BR4’s and had 5 failure to ignites. It was definitely easier sizing up without having to neck turn.

Were the BR 4s hard to seat?
The primers may not be seating properly.
If so run Remington 7 1/2 primers in your Alpha brass, as I do in the 6 Dasher...they will seat normally as the cup has a bevel to start and not square like the CCI and most others.
The Alpha brass has tight primer pockets, even with my 110 gr 3085 fps Dasher loads they will take awhile to loosen up.... stay with the Rem 7 1/2, they fire every time and produce small groups and are for high pressures, with their thicker cups, but no problem seating them, and they all go bang.

 

[MSBRPT]

Were the BR 4s hard to seat?
The primers may not be seating properly.
If so run Remington 7 1/2 primers in your Alpha brass, as I do in the 6 Dasher...they will seat normally as the cup has a bevel to start and not square like the CCI and most others.
The Alpha brass has tight primer pockets, even with my 110 gr 3085 fps Dasher loads they will take awhile to loosen up.... stay with the Rem 7 1/2, they fire every time and produce small groups and are for high pressures, with their thicker cups, but no problem seating them, and they all go bang.

I did notice they were harder to seat than what I’m used to. I’ll have to give the Remington’s a try.

 

[45-90]

I did notice they were harder to seat than what I’m used to. I’ll have to give the Remington’s a try.

I went through the same problem when I started, so I did an investigation, and found the problem.
You will be happy with the Rem 7 1/ 2.

 

[Floridapanhandle]

OAL?

BTW - I've been warned about increasing by "grain" amounts and ushered to only increase loads by fractions of grains due to how quick pressures spike in this particular case.

if you're looking to achieve ~10% velocity increase I was advised into .5gr max. increment increases (not sure if that applies to subs and supers or just one of those)

My OAL is 2.755
I've loaded up 5 each of 14.8g 14.9g and 15g. Next range trip will be in a couple weeks. I'll post my results then.

 

[MSBRPT]

I reloaded more converted Alpha 6 GT brass with SRP. I think I solved the FTF issue. I’m using a Q Fix that had a Q “hard spring” in it. It seemed to be working fine until recently. I swapped my BR4s out with CCI 450s and still had FTFs. Took out the “hard spring” and replaced it with one I know will work every time. Every primer fired. It still seemed like the primers were tight in the Alpha brass even after changing to 450s. I loaded a batch of 10 using N133, BR4s and 300 SMKs. Here’s a photo of the fired primers, one misfire (top left). Fired primers seemed to look like donuts, maybe pushed out slightly from the pocket. I loaded these without powder or a bullet, not sure if that causes this to happen.

 

[45-90]

They are pushed slightly out of the pocket because there is no force pushing the case back against the bolt face to seat the primer, like when an actual loaded round is fired.

 

[SigSauerM7]

Wow these hybrid casings are awesome.

Be funny to see what a 250gr Berger or SMK can do.

Pretty heavy hitters.

I wonder if 240 or 250 gr .30s cals would work?

250 ATIPs at like 2600 fps and you are 2000 yard transonic pretty well..

 

[tom12.7]

250's @ 2600 might be a stretch, but 160 TTSX @ 2600 in a 12" is doable pretty easy.

Edit to add that I have reduced these loads to something not as hot.

 

[DRWilson]

This data is all promising. I haven’t received my 6.5 twist barrel but should arrive in a month.

I posted earlier this year about my Faxon barrel being inaccurate. I was wrong. It’s actually accurate for me. But when I paired it with the CGS Hekate Suppressor, it was wildly inaccurate… like 20moa inaccurate at 100yds. No strikes or anything. CGS currently has the suppressor. Gorilla helped me troubleshoot this for me. I will still go to 6.5 twist.

 

[45-90]

Shot 2 338s today one 8.6 Blackout and one I chambered 338 RCM AR 10.
But this is about the 8.6 Blackout, got some high velocity figures, for those interested in that.
This is the 6.5 twist barrel as many know I have given up on the 3 twist. So I can shoot cheap bullts fast and accurate and shoot 300 gr subs accurately also.
These are hunting bullets most lead but copper too.
The 250 gr were right at 2200 fps tbe 225 gr at slightly over 2400 fps and the 160 gr Barns at 2800 fps.
The 225 and 230 gr would be a nice pick for larger big game, for energy and range...like the elk that hang out in the area.

 

[tom12.7]

Have you tried faster powders than H335 with the 160 TTSX?