8.6 BLK with 1:3 twist

Welcome to the Leverguns.Com Forum. This is a high-class place so act respectable. We discuss most anything here ... politely.

Moderators: AmBraCol, Hobie

Forum rules
Welcome to the Leverguns.Com General Discussions Forum. This is a high-class place so act respectable. We discuss most anything here other than politics... politely.

Please post political post in the new Politics forum.
Post Reply
User avatar
CowboyTutt
Advanced Levergunner
Posts: 3712
Joined: Tue Sep 11, 2007 8:27 pm
Location: Mission Viejo, CA

8.6 BLK with 1:3 twist

Post by CowboyTutt »

The times they are a changing! Curious about it. Parent case 6.5 Creedmoor. Way more powerful than either 300 BLK (or Bleck ) and 6.5 I believe. Lots of videos here.

https://faxonfirearms.com/86blk/

-Tutt
"It ain't dead! As long as there's ONE COWBOY taking care of ONE COW, it ain't dead!!!" (the Cowboy Way)
-Monte Walsh (Selleck version)

"These battered wings still kick up dust." -Peter Gabriel
User avatar
AJMD429
Posting leader...
Posts: 31932
Joined: Sun Sep 09, 2007 10:03 am
Location: Hoosierland
Contact:

Re: 8.6 BLK with 1:3 twist

Post by AJMD429 »

.
It seems like the psi would be crazy-high with that twist if you go supersonic.
Doctors for Sensible Gun Laws
"first do no harm" - gun control LAWS lead to far more deaths than 'easy access' ever could.


Want REAL change? . . . . . "Boortz/Nugent in 2012 . . . ! "
User avatar
wvfarrier
Senior Levergunner
Posts: 1440
Joined: Mon Oct 28, 2013 9:27 am
Location: West (by GOD) Virginia

Re: 8.6 BLK with 1:3 twist

Post by wvfarrier »

The article I read was claiming Sub 3" (subsonic) groups at 300 yards. If so, thats impressive
A bondservant of our Lord, Christ Jesus
User avatar
AJMD429
Posting leader...
Posts: 31932
Joined: Sun Sep 09, 2007 10:03 am
Location: Hoosierland
Contact:

Re: 8.6 BLK with 1:3 twist

Post by AJMD429 »

.
If you think about it, there are really three variables with firearms. The first one is the overall energy sent down range, which is going to determine more or less the requisite bulk of the firearm itself, as well as the amount of recoil. Once that threshold is determined, which essentially determines whether you are going to be dealing with a handgun, carbine, rifle, or some sort of mounted firearm, you have the classic trade off between mass and velocity.

It seems like the main two advantages of velocity are that it flattens trajectory, so if you don't know the distance to your target precisely, you have more leeway, and that for some hardened targets very high velocity is needed for penetration or to inflict the desired damage.

The main two advantages of mass is that for soft targets that you don't want to damage, but would rather eat, they do a better job, and that by being able to achieve a higher cross-sectional density within a given caliber, you will generally be able to maintain velocity better and if you are using supersonic velocities, be able to reach out farther before the bullet goes subsonic and destabilizes.

So I guess within a given energy range and firearm size, you can make a case for heavy-for-caliber bullets at slower velocities being better for long range targets, since once you get out very far, you pretty much have to know the range anyway, and at long ranges you generally have adequate time to determine the range if you have proper equipment. For closer range where rapid shooting is required without necessarily time for accurate ranging, or the target may be moving, it makes sense to be using lighter bullets at faster velocities to flatten their trajectory and make hits more likely.

So I guess if you can stabilize a long heavy bullet well enough, it can extend the range, and if you can launch it at a fairly high velocity within the weight-constraints of your firearm, it may be adequate enough for close rapid shooting as well. Certainly using a rifle and/or carbine chambered in such a round could reduce inventory and be versatile, especially if you could load reliable ammunition in both supersonic/light and subsonic/heavy ranges, for 'close' and 'far' targets respectively.

It is interesting to consider the tremendous kinetic energy that projectile has if it is moving even 1,000 ft per second which would mean it is rotating 240,000 RPM if rifling is 1:3"...! It may not alter the terminal ballistics effects much on a hard target, but I would think if that such a bullet tumbles or destabilizes in flesh it would be extremely destructive even if it were not a frangible or expanding type bullet.

Perhaps taking advantage of that is a way that the military sees to improve terminal ballistics without violating any rules about types of projectiles permitted.
Doctors for Sensible Gun Laws
"first do no harm" - gun control LAWS lead to far more deaths than 'easy access' ever could.


Want REAL change? . . . . . "Boortz/Nugent in 2012 . . . ! "
User avatar
Ysabel Kid
Moderator
Posts: 27790
Joined: Mon Sep 17, 2007 7:10 pm
Location: South Carolina, USA
Contact:

Re: 8.6 BLK with 1:3 twist

Post by Ysabel Kid »

Very interesting!!!
Image
User avatar
wvfarrier
Senior Levergunner
Posts: 1440
Joined: Mon Oct 28, 2013 9:27 am
Location: West (by GOD) Virginia

Re: 8.6 BLK with 1:3 twist

Post by wvfarrier »

One big downside is that .338 projectiles are extremely expensive and limited in options.
A bondservant of our Lord, Christ Jesus
User avatar
CowboyTutt
Advanced Levergunner
Posts: 3712
Joined: Tue Sep 11, 2007 8:27 pm
Location: Mission Viejo, CA

Re: 8.6 BLK with 1:3 twist

Post by CowboyTutt »

I don't think you can generalize between the .223 and the 8.6 mm however...

https://www.youtube.com/watch?v=_t7NQnKWyW8&t=190s

and P.O. Ackley did experiment with extreme fast twist barrels that led him to conclude no significant improvement in a super fast twist barrel. But this video is interesting to say the least, and a faster twist rate might offer an advantage in the bullet staying true to its trajectory through meat, but not necessarily damage.

-Tutt
"It ain't dead! As long as there's ONE COWBOY taking care of ONE COW, it ain't dead!!!" (the Cowboy Way)
-Monte Walsh (Selleck version)

"These battered wings still kick up dust." -Peter Gabriel
Post Reply