Sorry, Over & Under shotguns are not SASS or NCOWS legal.
SASS:
Any side-by-side or single shot shotgun typical of the period from approximately 1860
until 1899 with or without external hammers, having single or double triggers is allowed.
Automatic ejectors are allowed on single shot break action, lever and pump action shotguns
ONLY. Side-by-side shotguns may not use automatic ejectors. Lever action, tubular feed,
exposed hammer shotguns of the period are allowed, whether original or replicas. The only
slide action shotgun allowed is the Model 1897 Winchester shotgun, whether original or
replica. Certain shooting categories require a specific type of shotgun and ammunition to be
used. Military configurations are not allowed (i.e., trench guns). Please see the shooting
categories for further information.
NCOWS Approved firearms:
Shotguns, Reproductions
Winchester 1897 pumps by Norinco and Tri-Star
Side-by-Side/Double Barrels: approved models are too numerous to list here.
Winchester 1887 lever-action 12 ga.
IAC 1887 replica lever-action shotgun
IAC 1893 replica pump shotgun
Single trigger/ double-barreled shotguns
Top-lever break single shot shotguns that retain the characteristics of pre-1899 originals