WyoJoe-a best doesn't exist IMO but there are some really good choices that continually float to the top of the heap. R22, H4831 and either IMR4350 or H4350.
As for the question about R15 I'd use it with the 90's-110's but most likely not for the 130's.
Good luck to ya
Dober
+1
Altho H4831
Winchester casings
CCI 200's or Winchester 120's
and Speer, Hornady or Sierra flatbase 130's always worked well when first exploring a load and and new-rifle accuracy-potential.
I later learned to really like Nosler and Hornady 140's as an all-around weight.
BTW, Nosler 150-Partitions penetrate every bit as well as .30 cal 180-Partitions -
for elk!
