The Ramshot powders are all ball or spherical powders. While they all require a magnum primer for a good initial kick in the pants, they are at least as good as the Hodgdon Extreme powders and much, much cleaner burning. The double based Vihta Vuori (the 500 series)are up there as well as steady performance in temperature extremes. Reloder 15 is a good powder for use in temperature extremes. It was not always, but Uncle Sam insisted, and got his way. It is the powder used in all 7.62 NATO ammunition used by the United States military. It is good stuff. It is the only powder so far listed that works well with low pressure rounds like a Nitro Express round. It is Federal factory fill in their Nitro Express ammunition.

The old IMR series of powders still works very well at the lower pressures such as the 30-40 Krag, the 7x57 (older guns), and of course the .416 Rigby. With 400 grain bullets, IMR 4831 is tough to beat in this one. Many of these newer wonder powders do very poorly below 50,000 psi. Not so with the old IMR stuff. One look at the Speer manual in the .280 Remington spells this out. The Hodgdon and the slower Reloder series of powders don't do well below 50,000 psi and there are only 2 grains separating the top from the bottom load. My own shooting has verified this to be true whilst working up loads and noticing large quantities of unburned powder.

If your gun only shoots an IMR powder well you can debur your primer flash hole; and be fastidious. And use Federal primers. They seem less affected by temperature than other brands. This cuts the temperature affected velocity significantly. I use all brands of primers and have found that they all work well, but the Federals are less affected by temperature than other brands. I have seen this in print and verified this out for myself. It is not because they are the hottest. They are not, Winchester holds that title in the magnum and non-magnum large rifle category. CCI 450's and Remington 7 1\2's in the small rifle category.