These four powders would fit most of my reloading needs (both rifle and pistol):

In other words, if you had to stock up on powder and were limited to a half dozen or fewer, what would they be?

Will do most everything for pistol and rifle, respectively. Unique will do well in pretty much any pistol case. Maybe not excellent or perfect but usable. IMR4895 is nice because it's performance is very proportional down to about 60% (WARNING: from memory) of full loads. It's nice to be able to throttle back for plinking or new shooters.

Add others for more specific purposes, e.g., 2400 or H110 for rompin' stompin' pistols, IMR4831 for magnum rifles, etc.

H110
Unique
IMR 4064
760..748
Goes ff and fff

I think Hoot hit it.
I might add 2400 to that list, but the two he recommended will cover a really broad spectrum.

For my applications:
WW231/HP38
H335

WST & AA9 would also be good for my uses

IMR 4350
H4895
Unique
2400

All the rest just gets bought in one pound cans.

H4895 and Universal are all I need.

Else. I have a little of this and that (4064, Bullseye, 2400) and was trying to decide what I should be more serious about. Sounds like 4895 and 2400 are on my list. There are so many powders our there!

about any pistol/rifle cartridge - perhaps not the best choice for every case if you are seeking top performance, but they will work. I use both extensively.

Picking two more... probably H110/296/820 for heavy handguns and 300BLK. Weird selection for most, but my last one would likely be WC872 for cast rifle loads. However, 4895 is a good one also.

Others like Bullseye, 231, Blue Dot/#7, 2400, 1680, 3031, and WC852 get used in certain applications but are not as versatile, if I understand where you are going with this.

Also depends a lot on which cartridges you load.

on purpose... I did find a 5 pounder of Red Dot in AK. It is VERY economical and about all I load ACPs with for then last 7 years...I am on my second 5 pound ...still can't prove it by my shooting...;-/

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Of the Troops & For the Troops

Decently across the board. 357, 45 Colt, 9 mm, 45 acp, 223 & .30-06 (I know there is a big gap in rifle calibers...).

I use 335 in 223 and 35Whelan. Works pretty good in both, and meters well.

Unique, 2400, H4350 and H4198.

It would be hard to do without 335 as well. So I need 5