section_path: History/Firing mechanisms/Percussion cap
section_name: Percussion cap
paragraph_text: Percussion cap
  
  Percussion caps (caplock mechanisms), coming into wide service in the early 19th century, offered a dramatic improvement over flintlocks. With the percussion-cap mechanism, the small primer charge of gunpowder used in all preceding firearms was replaced by a completely self-contained explosive charge contained in a small brass "cap". The cap was fastened to the touch hole of the gun (extended to form a "nipple") and ignited by the impact of the gun's "hammer". (The hammer is roughly the same as the cock found on flintlocks except that it does not clamp onto anything.) In the case of percussion caps the hammer was hollow on the end to fit around the cap in order to keep the cap from fragmenting and injuring the shooter.
  
  Once struck, the flame from the cap, in turn, ignited the main charge of gunpowder, as with the flintlock, but there was no longer any need to charge the touch hole with gunpowder, and even better, the touch hole was no longer exposed to the elements. As a result, the percussion-cap mechanism was considerably safer, far more weatherproof, and vastly more reliable (cloth-bound cartridges containing a pre-measured charge of gunpowder and a ball had been in regular military service for many years, but the exposed gunpowder in the entry to the touch hole had long been a source of misfires). All muzzleloaders manufactured since the second half of the 19th-century use percussion caps except those built as replicas of the flintlock or earlier firearms.