I think the complete answer depends on the powder and the caliber in question. You will have to look at a load manual.
For your purpose, either bullet will work, but with the same powder charge a heavier bullet will have more power, regardless of its velocity. But, the heavy bullet will be slower.
For your purpose, either bullet will work, but with the same powder charge a heavier bullet will have more power, regardless of its velocity. But, the heavy bullet will be slower.