For many years I loaded 8K plus of 223 rounds for matches. That being said you can use lots of powders.

A few thoughts. Varget is usually a good powder and if you work up a load in a sweet spot(audette method that everyone should use anyway) a few tenths one way or another won't hurt. I know my guns still shoot sub MOA with thrown loads of Varget years ago when I still used that powder. And I know that I had variances of up to .3 grains.

WW748. Nice great powder. Extremely temperature sensitive.

AA powders-- vary so much from one lot to another at times that I'll never use em again unless I bought about 100 pounds at a time or more. YMMV. When I got 200 FPS variance and from great accuracy to no accuracy......

Surplus powders like from gibrass.com or patsreloading.com are worth looking at. But surplus IE military stuff can vary 10% in burn rate from one lot to another. So buy a bit at a time. WC 844 and WC846 are both worth looking at anyway.

All Reloader powders have been good. All IMR powders and all Hodgon powders good. All Viht powders good.

Thats about all I can add.

Jeff