Load Issue with 20 deg temp change?

[Raydee]

Watch all 12 vids from one of the BR masters

 

[quest450]

sorry Jeff, seems like my poor attempt at funny and sarcasm flew right over your head, myself and most of the ppl I shoot with do not use flags or tuners

 

[Doom]

I'm sure there is info somewhere but I couldn't find it. I had a good load at 50* now it's not so good at 70* - 6br 105s, 30 gr Varget. What to do?
ty Don

Not trying to pick on you but there is absolutely no real information in this question for any of us to evaluate. You say the load was good at 50 degrees and not at 70 degrees but how did you establish the "good" load". Number of rounds? Range? Velocity? What conditions were these shot in? Wind? Sun or shade?

One thing to consider is velocity variation manifests itself in barrel time which is related to barrel pointing due to barrel vibration. Even a bad load with good SD/ES can shoot well in some rifles. If your standard deviation varies more in the same load the load may not shoot as well if the barrel is moving in the faster portion of its vibration cycle.

 

[AlNyhus]

One thing to consider is velocity variation manifests itself in barrel time which is related to barrel pointing due to barrel vibration. Even a bad load with good SD/ES can shoot well in some rifles. If your standard deviation varies more in the same load the load may not shoot as well if the barrel is moving in the faster portion of its vibration cycle.

You've touched on something most either don't consider, overlook, or both.

Good shootin' -Al

 

[jpal]

What was the velocity change?

People blame the powder for changes in air density. Thick air the bullet goes slower, thin air it goes faster. The main reason people have to re tune is density.

Temp response of Varget at constant density is nearly flat across 50 to 60 degrees.

Where can I find information on how tuning varies with changes in air density?
Thanks!