jwrowland77
Member
Well, at least interesting to me.
Load:
.308 Win
155gr SMK Palma
44.5gr IMR4895
Winchester cases
CCI 250
OAL 2.900
When I originally tested this load, I tested it in the heat of summer. It was roughly 95 degrees out when I tested (I like to test loads in the heat that way I know the only way the pressure and MV might go is down due to cold temps). Results were MV of 2750fps avg with SD of like 16.
I had to sight in my daughters Christmas gift, a .243, this past weekend, so I decided to chronograph my load again to see what the results would be.
It was right around 40 degrees out this past weekend. I ran 20 rounds over chronograph, which was the same amount as used before. Rounds had been sitting in the garage and the cold for a couple of weeks. Test results were MV of 2744, with a SD of 11.
I figured with a drop in testing temps of 55 degrees, my MV would have been slower than what it showed.
So in my mind, the difference between hot and cold here with my loads using the IMR4895, is almost negligible.
Thoughts?
Load:
.308 Win
155gr SMK Palma
44.5gr IMR4895
Winchester cases
CCI 250
OAL 2.900
When I originally tested this load, I tested it in the heat of summer. It was roughly 95 degrees out when I tested (I like to test loads in the heat that way I know the only way the pressure and MV might go is down due to cold temps). Results were MV of 2750fps avg with SD of like 16.
I had to sight in my daughters Christmas gift, a .243, this past weekend, so I decided to chronograph my load again to see what the results would be.
It was right around 40 degrees out this past weekend. I ran 20 rounds over chronograph, which was the same amount as used before. Rounds had been sitting in the garage and the cold for a couple of weeks. Test results were MV of 2744, with a SD of 11.
I figured with a drop in testing temps of 55 degrees, my MV would have been slower than what it showed.
So in my mind, the difference between hot and cold here with my loads using the IMR4895, is almost negligible.
Thoughts?
Last edited:
