Higher elevation groups

[Peotone Joe]

I am shooting about a 1 1/4 inch group (2 tight and 1 high or left or right) with my 7 mag that has a 9 1/2 twist with a 175 grain Berger bullet. The calculator says (where I live 700 ft above sea lever) the twist should be 8 1/2. Where I will elk hunt it is 9300 ft above sea level. Will that group tighten up???? The calculator says it is at its max for being stable at 9300 ft.

 

[Fullbore92]

Have you chrono'd your load to see what your FPS is? I shoot 7mm mag a lot and typically I'll see my rounds start walking left or right whenever I let my barrel heat up too much.

 

[Peotone Joe]

I'm shooting 3056 ft per second. I shoot 3 and cool the barrel. I was wondering if I should just shoot the 162 ELDx which is good out of a 9 1/2 twist.

 

[Fullbore92]

I shoot a factory Savage with a 9.5 twist and the 162 ELD-X shoot great out to 600 for me. Haven't killed anything with them. The 168 Berger VLDH shoot best for my rifle and I wouldn't hesitate to use them for elk. Just my two cents. As far as groups tightening up at higher elevations, I'm not really sure.

 

[Peotone Joe]

I shoot a factory Savage with a 9.5 twist and the 162 ELD-X shoot great out to 600 for me. Haven't killed anything with them. The 168 Berger VLDH shoot best for my rifle and I wouldn't hesitate to use them for elk. Just my two cents. As far as groups tightening up at higher elevations, I'm not really sure.

Is that a Savage 110 High Country??? I have a Savage it does shoot great but it was too heavy for me so I bought a Tikka.

 

[Fullbore92]

It's just a basic 110. It's pretty light weight. Tikka was the better choice for sure. Those T3x actions are some of the smoothest I've seen.

 

[Tiny Tim]

Elevation will affect your external ballistics and may get you closer to a more acceptable stability factor, but I doubt it will change your group size to a large extent. What distance are you shooting (assuming 100 yards).

I've shot several bullets that were marginally stable (1.26-1.31) and not had any issues. If your third shot is always opening your group, it's likely due to heating of the barrel. Try letting it cool longer between shots, or try another bullet and see if the same problem persists.

 

[FEENIX]

I am shooting about a 1 1/4 inch group (2 tight and 1 high or left or right) with my 7 mag that has a 9 1/2 twist with a 175 grain Berger bullet. The calculator says (where I live 700 ft above sea lever) the twist should be 8 1/2. Where I will elk hunt it is 9300 ft above sea level. Will that group tighten up???? The calculator says it is at its max for being stable at 9300 ft.

SG, yes; group size, no.

 

[adk hunter]

In 2024 I think it is possible to cut that group size in half at least. I'd definitely change bullets and try some other brands too until you find what your barrel likes...

I have a few varieties if you want a sample pack shoot me a PM.

 

[BrentM]

Stability issues have a bit more to do with long range/down range performance as you near the transonic zone and the bullet is slowing down significantly. You'd have to be way out of whack to get a significant group size change.

Your flyer is either shooter induced or rifle induced. I had a 6.5-284 that did that crap all the time until I backed the load down just a touch and it became a bug holer.

 

[crashlanding]

Have you tried bergers bullet seating depth test to eliminate the flier?

 

[Beluebow]

SG, yes; group size, no.

This^^.......If it's junk at home it will be junk when you get where you're going.

 

[skipglo]

I'm shooting 3056 ft per second. I shoot 3 and cool the barrel. I was wondering if I should just shoot the 162 ELDx which is good out of a 9 1/2 twist.

Doesn't hurt to experiment.... why be limited to 1 bullet .... especially when it's teetering on the Edge!

 

[Peotone Joe]

Have you tried bergers bullet seating depth test to eliminate the flier?

yes. most of them did the same and a few would spread to 1 1/2. Nothing close to being good except for the ones from 3.32 to 3.24 those always had a flyer.....