It's not particularly temp-resistant, the reason I load H4198 in my .17 Hornet for hot-weather shooting.
What sort of ballistics are you getting?
got out with the chronograph this afternoon..
20 grains of AA 1680 with a Win Small Rifle primer in Remington Brass, with a 32 grain V Max..
results were:
1. 3666 fps
2. 3694 fps
3. 3679 fps
4. 3672 fps
brass expansion, was minimal.. neck sized it and it rechambered just fine...
maybe someone with Quick Load can do a pressure forecast for us..
outside temp was about 65 degrees and humid, and a thunderstorm was hot on the way... thundering and lighting in the distance... out on Forest Service land on a 4,000 mountain top...
