Yes, as long as the diameter of the ball is less than the bore diameter of the barrel. Understand that Wheelweights rarely expand on hitting flesh, and only a little when striking bones. They are a great way to get more penetration with a RB.
However, they tend to weigh less than a pure lead RB from the same mold, and will be sligthtly larger. Use scales to weight these, and sort them. Use a micrometer, or caliper to measure them, and to sort them. Alloyed lead tends to give a range of weights as cast, more so than pure lead does.
Because they are lighter in weight, using the same amount of powder often causes them to strike higher. You either have to adjust the sights, or your POA to hit the same POI on a target.
There was a recent article in Muzzle Blasts where the Bevel Brothers tested Wheel Weight balls and found them to be just as accurate, PROVIDED they are sorted by diameter and weight. Just remember that they will strike higher with the same sight setting you are using for pure lead balls.
Good casting, and great shooting to you. :thumbsup: