21 May 2025, 06:49
CouchTater300 TSX in 375 Ruger Guide Gun; powders?
As it says on the tin, I want to find out which powders will work well for a 300 gr TSX in the 375 Ruger. GG has a 20 inch barrel.
I want an available powder (i.e. not Alliant), minimal compression, and preferably moderate/low temperature sensitivity. I'm only looking for about 2500 fps.
Searching AR indicates Varget and H4350 might do. Haven't seen H4895 mentioned. My QL calculations, not to be trusted obviously, look like this;
68.25gr H4895, 67 kpsi, 2500 fps
70.25gr Varget, 67 kpsi, 2500 fps
76.7gr H4350, 65 kpsi, 2500 fps, 108% fill
68.25gr 8208, 70 kpsi, 2500 fps
Are these pressure predictions way off? What do y'all think are safe max loads with these powders?
thx
22 May 2025, 06:54
sambarman338I don't have your calibre but predict that H4895 and Varget will give you less-compressed loads (than 4350, at least) and good heat tolerance. Why, the latter? Because last I heard those Hodgdon powders were all made in sunny Australia and have a good reputation for withstanding torrid climates.
The faster powders are also more likely give best performance in your short barrel.
The pressures quoted seem a bit high for tropical loads, though.