ABM,
Using extruded powders, I'd have to say that IMR4064 and Varget are probably the two top powders. The burn rates on both are about identical, but Varget is a little more temperature tolerant. Meaning that velocities on loads that are built during one temperature, change very little when the temperature changes. They do, but not as much as other powders. IMR4064 is less tolerant to temp. changes.
I'd say that IMR3031 & IMR4895 probably would be very close seconds, as far as choices.
In the ball powder catagory, H380 would most likely be up there on top, with BLC2, H414 and W748 or W760 right up in there.
Where one powder works good in a certain gun, other's might not, so sorry to say, somtimes it requires picking up a few cans of different varieties.
If you want to narrow it down, reading these threads will give you a very good idea what works over a larger collection of guns.
If it were me, shooting from the hip, I'd grab a can of Varget & IMR4064, and maybe a can of H380, BLC2, or W748.
I've used BLC2 forever and it's always been a very accurate powder for most .22-250 loads I've ever used. It's what I started with in the 250'.
Many have touted that BLC2 & W748 are one in the same. I haven't run comparible loads with the two to find out how they perform side by each, but their load data indicates that this could be possible
BLC2 has worked well in loads that were pretty dismal with H380 (which is rare).
With most ball powders, it's been recommended that you use magnum primers as they are a little harder to ignite. I start with regular primers, and if I start to see vertical stringing, I'll switch. Otherwise, I'll leave them "as is".
Hope this helps you pard,
Good luck.......
Bob
