I have had the worst luck with Varget when temps change.
The velocity may stay the same but the groups did not and that is in my .223, .308, 30-06, and .243.
The old IMR 4064 groups stayed the same for my rifles and for my .223 H4895 was the ticket.
I have found another fun fact in my testing the more powder space you have the more difference you
will see in group size when the ammo changes temp.
This one is easy to test.
Shoot 4 rounds on a cool day with the ammo stored in a cool place out of the sun and single load each round but do not chamber that round until you have the rifle on target.
Now chamber it get on target as quick as possible and fire.
Do all 4 rounds as quick as you can single loading each one.
Chamber of the rifle should be pretty toasty.
Take that last round and chamber it and wait 2 minutes pull it out of the chamber
and see how warm it is now.
Probably much warmer than the other rounds.
Chamber it and fire it. See if it is in the group. If it is you are golden
My low accuracy node in .308 left a lot of air space and hot vs cold ammo really made you rethink the powder and load.
For my .223 and 5.56 a magnum primer gave better groups when temps changed.
CCI450 is all I use in those now.
Such a deep pit we fall into when handloading.
The velocity may stay the same but the groups did not and that is in my .223, .308, 30-06, and .243.
The old IMR 4064 groups stayed the same for my rifles and for my .223 H4895 was the ticket.
I have found another fun fact in my testing the more powder space you have the more difference you
will see in group size when the ammo changes temp.
This one is easy to test.
Shoot 4 rounds on a cool day with the ammo stored in a cool place out of the sun and single load each round but do not chamber that round until you have the rifle on target.
Now chamber it get on target as quick as possible and fire.
Do all 4 rounds as quick as you can single loading each one.
Chamber of the rifle should be pretty toasty.
Take that last round and chamber it and wait 2 minutes pull it out of the chamber
and see how warm it is now.
Probably much warmer than the other rounds.
Chamber it and fire it. See if it is in the group. If it is you are golden
My low accuracy node in .308 left a lot of air space and hot vs cold ammo really made you rethink the powder and load.
For my .223 and 5.56 a magnum primer gave better groups when temps changed.
CCI450 is all I use in those now.
Such a deep pit we fall into when handloading.
