Re: Hodgdon's "Extreme Powder" - reduce velocity variations due to temperature chan
I haven't tried H4350 or H4831. But I've run H1000 and Retumbo loads in 7mm Rem Mag, 300 Win Mag, and .280 RCBS Improved class cartridges over the chronographs in these two extremes:
1) Rifle and ammo stored in house @ ~70F and walk out the door to fire over chronographs located adjacent to the house.
2) Rifle and ammo stored in chest freezer @ ~0 to -5F, and pulled from chest freezer and fired over chronographs.
These two Hodgdon powders showed very little difference in muzzle velocity. The H1000 in the .280 RCBS Imp MV was basically the same.
The drop in velocity when I did the same test with IMR 7828 was dramatic, in comparison. But as I stated, I haven't tried it with H4350 or H4831. It all takes time and I'm currently not using those two powders in any hunting loads.