Called “back action” because the mainspring hangs behind the tumbler, this lock was popular on percussion guns made in St. Louis, New York, California, Ohio, England and Belgium. Swivel breech double rifles require a back action lock mechanism. This lock can be modified for flint use. Side-by-side or over-and-under double rifles, shotguns, and combination guns often use back action locks.

Makers of bench rifles, target rifles, slug guns and Sniper’s rifles of the 1840 to 1880 preferred these long thin locks.

These nice locks feature a fly detent, for use with set triggers. The mainspring and stirrup result in fast lock time, making this lock a good choice for the serious target shooter.

The hammer has a 1.625” throw for use with barrels from 13/16” up to 1-1/4”. Our left back action lock exactly matches our right lock. Notched at the tail to hook under a wood screw, we recommend that you use our #6 x 1/2” screw, set permanently in the lock mortise.

Strangely, some original back action locks are much different inside, with the mainspring along the bottom, hooking a link mounted at the front of the tumbler. This odd geometry permitted using a conventional sear spring. But sear placement is always the same.

Faced with the task of repairing rotted out right and left locks on a Belgian double shotgun that is otherwise serviceable, it may be easier to simply trim these lock plates to fit the existing mortise, or inlet these new locks. Retrofitting new locks is a gunsmithing challenge since hammers may need to be bent, shortened, stretched, or you may refit your original hammers.

This lock exactly matches our right hand back action percussion lock.

This lock is shown at exact-full-size, in Track's new catalog for gunmakers and gunsmiths.