The 'bullet's' shape is the standard Lee R.E.A.L. shape, which stands for: Rifling Engraved At Loading

The are made as production runs in .45, .50 and .58 calibres and are available in double cavity aluminum moulds w/handles for a paltry $25.99 - normally.

The bands are supposed to be progressively larger towards the nose, so that the bottom band slides into the bore, barely touching. The next engraves a bit, more, etc as you approach the nose, with the last one being the largest. This progressively larger bullet diameter helps to give a tighter fit inside the bore - so that: accuracy is increased and more importantly, the slug does not slide out the bore if the muzzle is pointed downwards. THAT is the danger of shooting slugs in ML rifles - rung/ringed or blown barrels are the result from displaced bullets at the moment of ignition. This slug, if fitting properly, should prevent movement.