Savage 12F/TR 308 winter / summer velocity difference

[tigrr]

I just checked the velocity of my 308 loads using 155 grain Lapua scenars, 45.7 grains of Varget, win case, CCI BR primers.
The velocity in the -5 to -18 range was 2925 to 2950 fps.
The velocity today at +12 C was 3058 fps.
The accuracy is the same, I just notice a little more kick, thats why I tested the velocity.
Anyone else found the same results using Varget?
I thought Varget was a less temperature sensitive powder.
Should I be concerned with the difference?

 

[vrmark]

hi tigrr
i have the same rifle i was at the range this weekend and with 45.7gr. rem brass cci primers varget an 155 vld's and i was 3012 on the crono. the temp was +23 c

 

[Mystic Precision]

If the drops are the same, then it might have been your chronie battery suffering from the cold.

If the gun is now shooting flatter, then the velocity gain is correct.

The Hodgdon powders are temp stable but not immune to temp. A temp range of almost 30C is about the same as 80F. Old tech powders would likely move more (SWAG 15 to 20fps for every 5 to 10F).

Jerry

 

[Moosetracker]

Are your loads with Varget from the same canister? Varget is notorious for varying density from batch to batch. I've have seen the same comment about speed variations related to Varget on other forums lately.

 

[Obtunded]

Are your loads with Varget from the same canister? Varget is notorious for varying density from batch to batch. I've have seen the same comment about speed variations related to Varget on other forums lately.

A-fricken-men!

I shoot in a winter league in which temps are typically well below freezing. I have to load develop for warm and cold weather.

The Varget comment is absolutely true. Buying 16 pounds from the same batch is now ritual for me, as the differences from lot-to-lot are horrendous.

 

[tigrr]

Its all the same lot. When I recieved the 2 - 7lb boxes of Varget I dumped them into a 5 gallon bucket and mixed them together. Then I put it into 8lb powder jugs.
I have to go out and see if the drop is the same at 1000 yards. Then I will know if it was the crono's battery or the powder is temp sensitive.
Then when I solve this I'll only have 999 other things left to figure out!