Hammerless

A hammerless firearm is a firearm that lacks an exposed hammer or hammer spur. Although it may not literally lack a hammer, it lacks a hammer that the user can pull.

In rifles, using a striker rather than a hammer is a substantial improvement because the time from trigger pull to firing can be less. This makes the rifle more accurate, because the rifleman's muscular tremors have less time to move the rifle off-aim.

One of the disadvantages of an exposed hammer spur is the tendency to get caught on items such as clothing; covering (shrouding, bobbing) the hammer by removing the spur reduces this tendency.

Early caplock firearms, patterned after their flintlock ancestors, had exposed hammers. The conversion was done by replacing the flash pan with a nipple for a percussion cap, and the flintlock's cock with a hammer to crush the cap and ignite the powder. The hammer was on the side of the firearm, easily reached for priming and cocking.

The earliest cartridge firearms simply copied the older style of action; the .45-70 "Trapdoor" rifle and most early cartridge double-barreled shotguns are good examples of this. In these designs, the loading of the cartridge(s) and the cocking of the hammer(s) were separate operations. While rifles evolved away quickly away from these early breech loading designs, the double-barrelled shotgun retained its popularity, and, for some time, its exposed hammers.

American inventor Daniel Myron LeFever was the first to develop a "hammerless" shotgun in 1878. It used internal strikers that were cocked manually, but in 1883, he developed a version that cocked the strikers automatically as the action was closed. This type of hammerless action, or the similar cock-on-open variation, is nearly universal in modern double-barrelled shotguns.

Early pump-action shotguns, like the lever-action rifles that preceded them, had exposed hammers. Most famous of these is probably the Winchester Model 1897. Like the double-barrelled shotguns, soon the early pump shotguns were replaced by models that enclosed the hammer completely in the action. Modern pump shotguns, with the exception of replicas of older exposed-hammer designs required in Cowboy action shooting, are all hammerless.

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