Actually, the motor oil and beeswax slugs will weigh more, and go further, than those plastic slugs you describe. That is why my father came up with the formula. He needed something that would shoot accurately to the top of his second story house, to reach the wasp nests under the gutters. Distance was between 15 and 20 feet. And, then, the slugs needed enough energy that they would knock off the nests before splatting against the bottom of the gutter, or against the soffit. The plastic slugs didn't work. The wax and oil slugs worked beautifully. He weighed them on his powder scale, but we are talking 50 years ago, and I just don't remember the different weights. He was using a .32-20 rifle, BTW, and not a .45 cal. MLer. Later he used his .357 Magnum, Single Shot rifle for this task. You only have to be stung once when you are at the top of an extension latter to appreciate being able to use a gun that made NO noise to shoot wasp nests down from gutters.