There is more to selecting a cast bullet than looks. It must "fit".
The diameters of the base and nose should be right. (nose fits across the lands, base fits the grooves.)
The first driving band should be in, or close to, the throat.
The base of the bullet should not protrude below the shoulder of the case. (gas cutting around the bullet)
The overall length of the loaded round is important for lever actions, in particular, and for magazine fit in general.
Proper nose shape. Flat point for tubular mags. Avoid spitzers.
If you are ordering cast bullets, specify the caliber that it is intended for.