This is a difficult question to answer. Most answers will be anecdotal. I’m not going to disagree with the guys that use the stuff because their results speak for themselves.

Let’s look at it strictly from a mathematical perspective in an effort to compare apples to apples. The weight of a pellet is determined by the volume multiplied by the density. Lead is 11.34 grams per cubic centimeter while TSS can be as high as 18.5 grams per cubic centimeter. If you find a chart that shows shot size diameter, you can quickly calculate the weight of each. What you will find is that a TSS pellet weighs approximately the same as a lead pellet that is 2 sizes bigger. For example a #6 TSS weighs about the same as a #4 lead pellet.

Assuming we are comparing apples to apples, if a lead #4 and a TSS #6 are shot at the same velocity, they will carry the same amount of energy, PER PELLET. The difference really comes in to play because the smaller TSS pellets allow for more pellets on the target.

When you start to look at the really small TSS sizes like #9 and #10, the discussion then becomes one of more pellets making up for reduced energy. These loads are capable of putting hundreds of pellets in a bird.