The cup-shaped cavity on the nose, which causes cavitation in the target material with a solid bullet, would prevent the mould blocks from opening. The rest of the design is OK by the appearance of it from the standpoint of making the mould- on a lathe or with a cherry.

As a flat nose with the rest of the design, it would work fine and give some minor expansion(dependingon alloy and hardness), but much care has to be practised when casting long bullets. They have a tendency to bend when contacting the folded towel or whatever is used to cushion the bulelts as they drop from the mould.