Varget is a very safe place to start (with hardly a chance you could overload with it) because it is on the slow end of suitable powders. (Varget will likely spray residue all over tha place- "unburned" powder.) The 4198s, OTOH, while good powders, are on the fast side especially for 400ish bullets. There are several powders in the "middle" of good burn rates which will work very well, getting good accuracy as well a maximum velocity potential. They include IMR 3031, RL 7, and H322 among others.