6.5 Berger 156 VLD and 8.5 twist barrel

[JLDavid]

I was wondering if anyone has tried 156s in an 8.5 twist barrel? I know Berger recommends an 8 twist. Was just curious if anyone had tried them in a slightly slower twist barrel. What powder did you use and what velocity range were you ooerating at? I will be hunting between 2000 and 4000' elevation. Not sure if this makes a difference in stabalizing these long heavy bullets. I have a 6.5-280AI for reference. Thanks and Happy New Year.

David

 

[Nomosendero]

Have you tried the various twist calculators such as the Berger?
I believe you will come up short.

 

[mikecr]

Without digging up specs for the bullet I could consider Berger's recommended as fully stable at 8tw under ICAO conditions (59degF, sea level). Sg of 1.50

8.5tw at ICAO would then lower Sg to 1.33 (marginal)
At std conditions for altitude of 2000ft ASL Sg = 1.41 (not bad)
At std conditions for altitude of 3000ft ASL Sg = 1.45 (plenty)
At std conditions for altitude of 4000ft ASL Sg = 1.50 (fully stable)

Keep in mind that standard conditions for those attitudes 2k to 4k are colder (52-45degF).
If actually warmer, stability goes upward.
I think you'll be ok no matter what.

 

[JackT]

I have a 8 1\2 twist 6.5 x 47, and I am considering the Berger 156 Elite Hunter as a potential elk load. My thought process is that if I can get the accuracy and velocity I want here in the Texas Hill Country, then it would only get better where elk will be found. Is there a flaw in that strategy?

 

[boltfluter]

I have a 8 1\2 twist 6.5 x 47, and I am considering the Berger 156 Elite Hunter as a potential elk load. My thought process is that if I can get the accuracy and velocity I want here in the Texas Hill Country, then it would only get better where elk will be found. Is there a flaw in that strategy?

Possibly case capacity could be a problem. A very long bullet pushed way back into a relatively small case. Just a thought.

Paul

 

[JLDavid]

I have a buddy that has some. When I get some brass formed up I am going to try some. What powders are most people using with them?

 

[JackT]

Yes I agree with you Paul...
...case capacity will limit velocity
...velocity (or the lack of it) will limit range
I look forward to testing a few loads and then sharing

..need to go find some now.

 

[FeMan]

I have a 8 1\2 twist 6.5 x 47, and I am considering the Berger 156 Elite Hunter as a potential elk load. My thought process is that if I can get the accuracy and velocity I want here in the Texas Hill Country, then it would only get better where elk will be found. Is there a flaw in that strategy?

FWIW, I used the 156 EOLs this year hunting antelope. My 6.5 SAUM shot them well and the MV was 3200+. Unfortunately, I hit my antelope just behind the shoulder and the bullet did not open up at all. I was able to shoot him again with a 143 ELDX in the neck and save the day. That is only the second bullet I have even had fail on me in 40+ years meat shopping. I still shoot these bullets in tactical and F-class but wont be hunting with them. Elk are much heavier if you can keep it in the shoulder but thayt 6.5x47 will be 500 or more fps slower than I was shooting them......

 

[LCazador]

I was wondering if anyone has tried 156s in an 8.5 twist barrel? I know Berger recommends an 8 twist. Was just curious if anyone had tried them in a slightly slower twist barrel. What powder did you use and what velocity range were you ooerating at? I will be hunting between 2000 and 4000' elevation. Not sure if this makes a difference in stabalizing these long heavy bullets. I have a 6.5-280AI for reference. Thanks and Happy New Year.

David

I shot them at a grand out of my 6.5/284 Shehane 8.5 twist and I was never happy with them. So when it came time to rebarrel I went to an 8 twist and voila I'm happy now! Beauty is in the eyes of the beholder. I shoot at 2800 feet altitude. You're stabilizing length and speed does not help per Brian Litz.

 

[JLDavid]

Thank you for all the replies guys. Looks like I will stick with the 140s for now.

 

[kfreeze]

I have a buddy that has some. When I get some brass formed up I am going to try some. What powders are most people using with them?

Rl26 gives good velocity with 156 bergers in a long throated 6.5×47. 2800 fps.

 

[barefooter56]

I was wondering if anyone has tried 156s in an 8.5 twist barrel? I know Berger recommends an 8 twist. Was just curious if anyone had tried them in a slightly slower twist barrel. What powder did you use and what velocity range were you ooerating at? I will be hunting between 2000 and 4000' elevation. Not sure if this makes a difference in stabalizing these long heavy bullets. I have a 6.5-280AI for reference. Thanks and Happy New Year.

David

David,
Altitude , velocity and temperature affect bullet stability . Of the 3 ALTITUDE is the biggest factor for making up for lack of twist rate. I ran you info thru our website TWIST RATE CALCULATOR https://bergerbullets.com/twist-rate-calculator/ . At 2000 FT your SG ( STABILITY FACTOR) is 1.34 . At 4000ft its 1.45. In both instances the bullet will be stable. BUT the BC is compromised so external factors like wind ETC can have more affect on the bullet than they would at full BC at 600 yards and beyond.

 

[deadidarren]

Have you tried the various twist calculators such as the Berger?
I believe you will come up short.

First thing I would have done.
And have done before I even build a rifle and calaber for twist .