6.5 bullet choice

[ErikET]

Anyone shot these Sierras from Mead?

Yeah couple hundred, my reloading setup is still a bit basic in terms of scale/brass prep but they grouped quite nicely. They're not Bergers, but I was very pleased. Looks like they're sold out again.

 

[6.5 forever]

Yeah couple hundred, my reloading setup is still a bit basic in terms of scale/brass prep but they grouped quite nicely. They're not Bergers, but I was very pleased. Looks like they're sold out again.

Thanks for the info.

 

[Laurie]

Used both 142 SMK and the 144 Hybrid. Both shot small at close yardages. But at 1 mile the SMK blew the Berger away. No idea why, but it did

The 142 SMK has a smoother transition than the Berger. Like an artillery shell. Looks like the Berger would try to tumble sooner as it slows down. Just looking at them. I spend a lot of time looking at the abstract so It might sound like I'm just bowing smoke.

In the latest edition of Bryan Litz's 'Applied ballistics for Long range Shooting' book, he has a short chapter on ELR external ballistics. He makes the case there that longer/'pointier' high-BC bullets have problems at extreme ranges as they suffer from 'dynamic stability' issues. This is different from gyroscopic stability which can be addressed by increasing the rifling pitch and bullet rotation rate. Shorter, blunter designs which are inferior due to their lower BCs at 'normal' distances (up to 1,300 / 1,400 yards IIRC) perform better at longer distances.

This was published some years ago when ELR competition was in its infancy, and I've no idea whether this hypothesis has been validated, or disproven, by experience. Litz said separately of ELR ballistics and competition that in his view, success would be about 'managing trans-sonic speed behaviours' which implies you mustn't go subsonic.

 

[X-Caveman]

Yeah couple hundred, my reloading setup is still a bit basic in terms of scale/brass prep but they grouped quite nicely. They're not Bergers, but I was very pleased. Looks like they're sold out again.

They must be getting down towards the end. They were out, available, out, and just now available again. If you haven't got in on them, better hurry!

 

[Steve Donlon]

In the latest edition of Bryan Litz's 'Applied ballistics for Long range Shooting' book, he has a short chapter on ELR external ballistics. He makes the case there that longer/'pointier' high-BC bullets have problems at extreme ranges as they suffer from 'dynamic stability' issues. This is different from gyroscopic stability which can be addressed by increasing the rifling pitch and bullet rotation rate. Shorter, blunter designs which are inferior due to their lower BCs at 'normal' distances (up to 1,300 / 1,400 yards IIRC) perform better at longer distances.

This was published some years ago when ELR competition was in its infancy, and I've no idea whether this hypothesis has been validated, or disproven, by experience. Litz said separately of ELR ballistics and competition that in his view, success would be about 'managing trans-sonic speed behaviours' which implies you mustn't go subsonic.

Thanks

 

[Kracken McGraw]

They must be getting down towards the end. They were out, available, out, and just now available again. If you haven't got in on them, better hurry!

I believe they’re gone. When you try to add them now it says no longer available.

 

[Kracken McGraw]

^^^^^ I should have to eat my hat, because those SMK at Meade are showing back in stock again this morning. Maybe it’s the way their site updates itself or something.https://meadammo.com/product/sierra-6-5mm-mk-142gr-bthp-bullets/

 

[6.5 forever]

^^^^^ I should have to eat my hat, because those SMK at Meade are showing back in stock again this morning. Maybe it’s the way their site updates itself or something.https://meadammo.com/product/sierra-6-5mm-mk-142gr-bthp-bullets/

Maybe just packaging a massive lot as needed.

 

[Kracken McGraw]

Maybe just packaging a massive lot as needed.

That’s makes the most sense.

 

[Nvcnvc]

Here are Amy experiences with both those bullets:
The gun is an Altus made gun in 6.5 Creed with Impact Precision, CRB 28" Competition contour barrel, B& A trigger, and Eric Cortina break. Very heavy at 25#s...
I usually do seating depth first before a powder ladder.
Best seating depth for 142s was at -28/000 and -3/000 for 144s.
Powder ladder decided 41 gns of H4350 for both.

142 SMKs
at 100 yds 3 separate strings of 5 shots varied from .22" to 0.30" (barrel was cooled to ambient temp between strings).
Then I shot a string of 10 at 600 with 4.5" vertical (I did not pay attention to horizontal as the winds were switch but not very strong).
Then I simulated a 20 shot string (shot within 20 minutes) at 600 yds again. The vertical jumped to 6.5" which is probably expected as the barrel heated up during the last 10 shots.

144 Bergers
at 100 yds 3 strings of 5 varied from .13" to .21".
I moved to 600 yds and shot a 10 shot string ( on another day and after I fouled a clean gun with there foulers). The vertical was 3.8".
I haven't shot a simulated 20 string shot yet with 144s, so the comparison is not yet apples to apples.

My thoughts so far:
I am not 100% sure, but the 144s might hold a better vertical at 600 or 1000 yds. I will have to test and confirm that thought of course, but that is my experience so far.
Of course you may have a different experience in your gun. Unfortunately unless you do some serious testing on your own, you will never know which one is better for your gun. good luck

 

[6.5 forever]

Here are Amy experiences with both those bullets:
The gun is an Altus made gun in 6.5 Creed with Impact Precision, CRB 28" Competition contour barrel, B& A trigger, and Eric Cortina break. Very heavy at 25#s...
I usually do seating depth first before a powder ladder.
Best seating depth for 142s was at -28/000 and -3/000 for 144s.
Powder ladder decided 41 gns of H4350 for both.

142 SMKs
at 100 yds 3 separate strings of 5 shots varied from .22" to 0.30" (barrel was cooled to ambient temp between strings).
Then I shot a string of 10 at 600 with 4.5" vertical (I did not pay attention to horizontal as the winds were switch but not very strong).
Then I simulated a 20 shot string (shot within 20 minutes) at 600 yds again. The vertical jumped to 6.5" which is probably expected as the barrel heated up during the last 10 shots.

144 Bergers
at 100 yds 3 strings of 5 varied from .13" to .21".
I moved to 600 yds and shot a 10 shot string ( on another day and after I fouled a clean gun with there foulers). The vertical was 3.8".
I haven't shot a simulated 20 string shot yet with 144s, so the comparison is not yet apples to apples.

My thoughts so far:
I am not 100% sure, but the 144s might hold a better vertical at 600 or 1000 yds. I will have to test and confirm that thought of course, but that is my experience so far.
Of course you may have a different experience in your gun. Unfortunately unless you do some serious testing on your own, you will never know which one is better for your gun. good luck

Good write up!!
Thank you.