Don’t let the slide slam forward on a 1911 if you can avoid it. They are typically designed to have a round in the chamber when they engage which slows and buffers the impact significantly. A few times, here and there is not a big deal, practicing repeatedly (racking the slide) on a 1911 can cause excessive wear on internal parts, specifically the “disconnector” which usually results in a multi-shot pistol.
Older firearms, anything with a fixed firing pin and rim-fire guns should not be dry fired. Fixed firing pins (typically revolvers where the firing pin is part of the hammer) can be damaged as the pin is designed to strike the primer of a cartridge. Without the cartridge in the cylinder, the forward movement of the hammer freely strikes the hammer nose bushing and the frame which places excessive stress directly on the hammer. Rim-fire guns can actually damage the chamber as the firing pin is designed to strike the cartridge rim vice the primer in a cartridge center.
Nearly every other modern semiautomatic pistol has a free-floating firing pin. You will not damage them by dry firing them. Use of a snap cap will solve any concerns you have if you remain unconvinced. I’ve been dry firing my guns for more than 25 years and none show any deleterious effects.
There are many types of Snap Caps on the market but the better ones are made of aluminum. “AZoom” snap caps are the most common (and the most expensive). AZoom snap caps are made of an aluminum casing with a rubber inert primer and plastic projectile nose. The aluminum casing and rim provide the most consistent feeding from the magazine to the chamber and will not damage your pistol. The rubber inert primer absorbs the shock of the firing pin impact. The next best choices are nickel or brass casing snap caps. Soft metal on tool steel is not much of a risk, but if you’re concerned – go with the aluminum.
Don’t waste your money on the cheaper plastic ones, they simply do not last. The plastic cartridge rims wear quickly. Also, if mixing live ammunition with snap caps for malfunctions drills or trigger controls drills, the heat from the hot chamber will expand the plastic. Typically, the rim will break off leaving the round stuck in the chamber. Then you get to punch it out with a rod… Plastic snap caps are just a bad material solution.
If you’re serious about getting better with your firearm, dry practice is critical to your success and snap caps are probably the cheapest training tool you can buy to improve your shooting!
~ Chris White