They were activated by tripwires connected to the firing mechanism. An advantage to the matchlock firing mechanism is that it did not misfire. The first designs were criticized as having a slow and cumbersome firing mechanism. This included diagrams of how to alter the firing mechanism for different firearms. Only the barrel, bolt and firing mechanism were precision machined. This allows easy access to the firing mechanism for cleaning. The Model 1803 used a flintlock firing mechanism. Charleville muskets were muzzle-loaded and used a flintlock firing mechanism. The receiver also houses the firing mechanism. Then Crypto manages to sabotage the weapon's firing mechanism. The rifle was muzzle loaded, and used a percussion lock firing mechanism. The Model 1717 also standardized the smoothbore barrel and flintlock firing mechanism. A hammerless weapon is a modification of the original firing mechanism of firearms. Each barrel had its own firing mechanism. It also uses double triggers and an enclosed firing mechanism.