Got a double this morning......

[Sendero_Man]

105 berger, 115 dtac.

I choose the 105 Amax for the performance on game, not paper.

getting 2.37" groups at 500 yards...

3036 fps here at 4600 asl. was shooting 3140, but I backed it down to next accuracy node to run the HV reticle in the NF compact.

 

[SBruce]

So you're getting 2.37" groups at 5 with the A-Max?? Or was that with one of the others? I was thinking of trying the Berger Hunting bullet (95grn) first. Have had great accuracy and performance on yotes with the 55 grn Berger MEF in 22-250 out to 500 yds.

Assuming the A-Max drops our song dogs DRT? Good expansion rate? I've never tried any.

Are you using H 4350 Powder? I've read that it and RL-17 and VVN 550 seem to be the most popular.

I'll be looking for some low ES's and Thermal Stability. Supposedly, H 4350 is an extreme powder and shouldn't be temp sensitive..........have you noticed much velocity deviation due to sub zero temps VS 40 degree days??..............Or winter VS summer for that matter?

Supposedly, the AI version is capable of pushing the 105's at 3200-3300 FPS, but I'll load it for accuracy and low ES's more so than top speed.

Thanks Scott

 

[Sendero_Man]

So you're getting 2.37" groups at 5 with the A-Max?? Or was that with one of the others? I was thinking of trying the Berger Hunting bullet (95grn) first. Have had great accuracy and performance on yotes with the 55 grn Berger MEF in 22-250 out to 500 yds.

Assuming the A-Max drops our song dogs DRT? Good expansion rate? I've never tried any.

Are you using H 4350 Powder? I've read that it and RL-17 and VVN 550 seem to be the most popular.

I'll be looking for some low ES's and Thermal Stability. Supposedly, H 4350 is an extreme powder and shouldn't be temp sensitive..........have you noticed much velocity deviation due to sub zero temps VS 40 degree days??..............Or winter VS summer for that matter?

Supposedly, the AI version is capable of pushing the 105's at 3200-3300 FPS, but I'll load it for accuracy and low ES's more so than top speed.

Thanks Scott

Yes, that group is with the 105 Amax off a bench on steel. My barrel is a 7.5 twist to handle the heavy higher BC bullets at our altitude and temperature.

105 Amaxes have given me great performance so far. All DRT if I do my part.

Yes, I am using H4350. Only got 19 fps difference on 74 degrees to 17 degrees over my Chrono.

I am not a RL powder fan, as I have found way to much shift from lot number to lot number when using RL in my 243AI.

 

[SBruce]

Very Interesting................243 Ackley was my initial thought for the re-barrel.
Gunsmith kinda recommended the Lapua.

Do you like the 6X47L better? Do you get better accuracy with it? Guessing that the 243AI was a little faster. What twist do you have in it? If you had them both in the same rifle, would you have a preference?

I heard a rumor that 4350 isn't so good at temp changes when they go below Zero. You heard anything about that, or noticed any change in POI when it's really cold?

Thanks again.

 

[Sendero_Man]

Very Interesting................243 Ackley was my initial thought for the re-barrel.
Gunsmith kinda recommended the Lapua.

Do you like the 6X47L better? Do you get better accuracy with it? Guessing that the 243AI was a little faster. What twist do you have in it? If you had them both in the same rifle, would you have a preference?

I heard a rumor that 4350 isn't so good at temp changes when they go below Zero. You heard anything about that, or noticed any change in POI when it's really cold?

Thanks again.

The 6x47 is inherently accurate, like the 6br and others. the long neck is better than the 243AI. I got great accuracy with the 243AI, but the 6x47 is even better !

7.5 twist as stated above for the barrel. any slower and it will not stabilize in our temperature/altitude for the 115 grain bullets. I am shooting 6x47 at 3036 and my 243AI at 3178fps. fps isn't important to me if it ain't accurate ! 6x47 is my preference over the two calibers.

Never had any problem with H4350 at all. Hunting coyotes in -21 and never a bit of trouble. I use magnum primers year around....

good luck.

 

[SBruce]

Sounds like I'll probably be pretty satisfied with the 6X47L. Gunsmith suggested that I go with 1-9 twist, because I'll probably only go up to 105 grn max. Hopefully that will be fast enough twist. I had not heard of the Altitude/Temp. having an effect on bullet stability/twist rate, ect. I heard that faster velocities can allow a slower twist, and that most rifling twists are based on 3000 FPS. Is there a link or reference to some more info on that??

Again, Thanks for your time and info.

OH, on another note; does Lightforce have a roof mounted spotlight kit/system??

 

[Sendero_Man]

Call David Tubb and talk altitude/temperature threshold !

and yes on the light.

Portable Systems

check out this link.

and do call David and ask about that. Superior Shooting Systems.