Got a new to me .30-06 that I intend to load up with 180gr partitions for elk this fall. I have both of these powders on hand. Any advantage to one over the other?
Have used IMR4451 considerably in cartridge/bullet combinations where I have also used both H4350 and IMR4350. Found 4451 worked at least as well, and often better, both in accuracy and velocity. The velocity part is probably due to 4451 being a double-based powder, rather than single-based like both H4350 and IMR4350. (That added touch of nitroglycerin does provide some extra zip.) 4451 also contains a decoppering agent, unlike either of the 4350s.
The present load I use in my New Ultra Light Arms .30-06 is 56.0 grains of IMR4451 with the 175-grain Barnes LRX--which is the maximum charge listed by Hodgdon with the 175-grain Sierra HPBT. The first 3-shot group at 100 yards measured right around half an inch, and it's shot the same way ever since. Velocityfrom the NULA's 24" barrel is a little over 2800 fps.
