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Gallery
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Clock-Type Spring
Patented during the Civil War, the Mershon & Hollingsworth mechanism involved a clock-type spring wound with a fold-out handle.
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Normal Fire
The button on the winding plate is a lock-out latch that allowed "normal" revolver operation.
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Hammer Block
A manual hammer-block latch prevented the hammer from cocking while the spring was being wound.
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Assembly Button
A small tab on the latch engaged a step on the hammer. Note the hand-checkering on the latch assembly button.
At the dawn of mechanized warfare, the U.S. Military contended with the reality that infantrymen would need an effective arm to defeat tanks. Their idea? Bring more gun.
For nearly 25 years, Springfield Armory has offered its affordable and reliable XD series of handguns, and for 2026, that design has now entered its fourth generation with the Mod.4 OSP.