In the front part of the manual, in the chapter on bullets, they have a chart depicting each bullet they offer in exact size. in the box with each bullet, they give bullet dimensions, a number that represents sectional density, and two velocity figures. The low figure represents the minimum velocity the bullet should be traveling when it reaches the target animal, to ensure the bullet will expand reliably. The high figure represents the highest velocity the bullet should be traveling when it reaches the target animal, to ensure the bullet doesn't come apart/shed the jacket, resulting in poor penetration.