The temperature sensativity issue is more prevelent with respect to pressure spikes caused by hot conditions.
Cold weather ignition is more a combination of chosing the correct primer, and burn rate than any specific manufacture of powder.
The only way to assure good results for cold weather operation is to work loads in cold weather, that is a for sure.
You'll likely be settling on more than one powder with your calibers listed, but on that read my sig line.
270 and 300 try something like 4831 (either blend)maybe 7828
For the 7mm-08, Varget, 4064, or maybe either 4350.
For primers I'd get as far way from development with Federal primers because they are so dang hard to get these days. I'd lean towards the Winchester offerings, possible Magnums even in the 270 (the 300 is a for sure), and regular LR's in the 7mm-08.
But, cold weather evaluation is the only way you will know what is gonna work in cold weather.
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There are no absolutes
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