8.6 BLK Thread

[DadSmith]

Looks like a 40 Super with a much longer neck. Cute project.

The important thing to remember about the 8.6 is that it's rotational velocity from a 1:3 twist significantly increases energy on target. A 1:6.5 barrel in the Razerback wont get that.

What is the speed of the rotation. I read it somewhere but have forgotten. I remember it being crazy fast.

 

[Aszerigan]

What is the speed of the rotation. I read it somewhere but have forgotten. I remember it being crazy fast.

Bullet RPM = MV X 720/Twist Rate (in inches)

For a subsonic - 1050 x 720/3 = 252,000 rpm (300gn Matchking)
For a supersonic - 1970 x 720/3 = 472,800 rpm (210gn Barnes TSX)

For comparison -
308 supersonic - 2800 x 720/12 = 168,000 rpm

 

[Jarvitron]

My 12" 8.6 just got approved and I need to go pick it up, I am v. excited.

 

[indyblue]

Bullet RPM = MV X 720/Twist Rate (in inches)

For a subsonic - 1050 x 720/3 = 252,000 rpm (300gn Matchking)
For a supersonic - 1970 x 720/3 = 472,800 rpm (210gn Barnes TSX)

For comparison -
308 supersonic - 2800 x 720/12 = 168,000 rpm

Wow, that is pretty fast. Are those jacketed rounds if they are I’m surprised they can survive spinning that fast. That’s faster than a turbo charger impeller.

 

[Jarvitron]

Wow, that is pretty fast. Are those jacketed rounds if they are I’m surprised they can survive spinning that fast. That’s faster than a turbo charger impeller.

I've seen some lively debate about if you should use jacketed bullets at all, and I think a good argument to be made that for supersonics you should just go all-copper only.

 

[rb288]

I say go for it.

The Hybrid 46 is 0.95" shorter than the Porq Chop so there's a better chance of a strike on a longer can. With the exit aperture being the same, it should be perfectly safe. And yes, it will be more quiet.

FYI......
The 30 cal endcap works just great and actually seems to be quieter than the porq chop on the 16" bolt gun with supers.
Just thought you might like to know.

 

[Aszerigan]

FYI......
The 30 cal endcap works just great and actually seems to be quieter than the porq chop on the 16" bolt gun with supers.
Just thought you might like to know.

Excellent. Great news. :-)

Thanks for letting me know. What muzzle device are you using? 46cal ASR?

 

[Aszerigan]

I've seen some lively debate about if you should use jacketed bullets at all, and I think a good argument to be made that for supersonics you should just go all-copper only.

Never use jacketed bullets for supersonic 8.6. Solid coppers only. Jacketed bullets will explode on exiting the barrel.

They're fine for subsonic. I shoot them daily.

 

[Aszerigan]

My 12" 8.6 just got approved and I need to go pick it up, I am v. excited.

 

[rb288]

Excellent. Great news. :-)

Thanks for letting me know. What muzzle device are you using? 46cal ASR?

No, the .338 asr brake.