All around powder or powders?

[Catfish]

When one says that them have a good alround powder that they use in all of their rifles that means that all of their rifles preform well with powders that are very close in burn rate. Rounds that have a similar case volume to bore diameter use powders of a similar burn rate. Case with a low volume to bore diameter use the faster burning powders. Cases with very large case volumes to bore diameter preform best with slow burning powders. The .223 and .308 share several powders with which they both preform well, and like wise with the .257 and 7 mag. If you try to use juse 1 powder for all 4 rounds the 1 that preforms best in all will preform well in any. If you reall want to keep down the number of different powder you buy I would you still get at least 2 kinds of powder.