FWIW - there's not a single one pictured in George Neumann's "Weapons of the American Revolution." (Mine came with it as basic hardware, so I'm stuck with it.) In any case, reenacting there is no need to set a hair-trigger, regardless of time-period. Now back to your regularly scheduled programming...
Pine River Boys, Co I, 7th Wisconsin
"We're... Christians, what read the Bible and foller what it says about lovin' your enemies and carin' for them what despitefully use you -- that is, after you've downed 'em good and hard."
-Si Klegg and His Pard Shorty