Provide a soft surface for the bullets to fall upon after releasing them from the mould, as they are easily deformed while hot. The sliding top or "cut-off" should be operated by pressing down the lever end on a board or table, or striking the lever with a small wooden mallet. The mould is then opened, and the bullet drops out. If the bullet sticks in the mould, strike the empty half of the mould on the outside, directing the blow toward the bullet. This will jar the bullet out of the mould without difficulty. Never strike the mould with a hammer or any hard substance, and never attempt to pry a bullet out of the mould or touch the interior surface with an iron implement, tool, or anything that will mar it. The least indentation of the sharp edges of the mould will cause the bullets to stick and make them imperfect. After using the mould, oil the exterior and the surfaces of the joint while warm, wrap in a dry cloth, and keep in a dry place where it will not rust. It is a good plan to leave the last bullet (with the neck cut off) in the mould until used again.
The fit of the bullets is very important. Nearly all the bullets for revolver cartridges were originally designed to be used with black powder. Many of them were slightly under size and have concave bases which upset sufficiently, on the ignition of the regulation powder charge, to fill the grooves of the barrel. Reduced charges of black powder, and smokeless powders, even in full charges, seldom upset the bases of these bullets, and the powder gas escapes around the sides of the bullet, which is known as "gas cutting." This is fatal to accuracy. For smokeless powders and reduced loads the concave cavity at the base of the bullet must be large enough to reduce the thickness of the outer rim of the bullet and weaken it so it will be expanded sufficiently by the powder to fill the grooves of the barrel; or the diameter of the bullet should be increased so as to produce the same effect.
A simple test to determine the fit of the bullet is to force it into a clean barrel, and then hold the barrel in the direction of a window or bright light. If light can be seen in any of the grooves around the bullet, it is too small for smokeless powder. The remedy is to have the bullet mould reamed out and enlarged so the bullets will be the proper size.