One tool used to scout hunting territory is a set of binoculars. This applies to telescopes, as well. A 7 X 35 binocular has seven times the magnification with a 35mm objective lens. Exit Pupil refers to the size of the shaft of light transmitted to the eye. The more light, the better the contrast.
Exit pupil is expressed in millimeters and divided by seven.
Therefore, the exit pupil is 5 mm in the 7 X 35 binoculars. Bullets made by casting a lead alloy in a mold are fine for short-range shooting, and sometimes for small game hunting. The use of casts bullets is limited. They can be used in low velocity firearms because the heat generated by high velocity cartridges would melt or deform them before the bullets cleared the barrel. Usually, a hard alloy cup, called a gas check, is fitted to the base of the cast bullet to protect it from heat and pressure, and serves to increase velocity.