- Must be of the period from approximately 1860 until 1899 without automatic ejectors.
- May be original or a replica.
- Side by side shotguns must be centerfire of at least 20 gauge and no larger than 10 gauge.
- Side by side centerfire shotguns in .410 gauge are allowed in the Buckaroo Category only.
- Modifying the firing, cocking, or chambering mechanisms in any way that changes the process from an entirely manual operation to any other style operation (i.e. blowback operation, gas operation or recoil operation) is expressly prohibited.
- Shotgun may have external or internal hammers.
- Shotgun may have single or double triggers.
- Shotgun barrels must be minimum 18 inches long. A longer barrel is allowed.
- Shotgun barrels may have internal choke tubes installed provided they do not extend beyond the muzzle.
- Shotgun trigger guards may be wrapped with leather or other natural material.
- A slide on leather cover to protect the offhand from barrel heat is allowed.
- Leather on a pump shotgun’s fore end or grip surface is not allowed.
- A permanently fitted, non-adjustable, lace on or slip on recoil pad is allowed on the buttstock of shotguns.
- Checkering, carving or laser engraving is allowed on fore-stocks and buttstocks.
- Bending the trigger guard on side by side shotguns so triggers are more exposed is not allowed.
- Contemporary rubber grips, modern target grips, grip tape and the like are not allowed.
- Front sights may be a bead or a simple post type sight.
- A light bead blasted finish may be applied to the exterior of a shotgun.
- Factory screws may be replaced with socket head cap or other type screw.
- Break action shotguns may add or modify internal mechanisms to guarantee side by sides to not close accidentally.
- The open angle for side by sides may be increased.
May be used in following categories: Traditional, Modern, Duelist, Gunfighter, Frontiersman if loaded with blackpowder, Classic Cowboy/Cowgirl if it has external hammers, B-Western, Young Guns, Buckaroo, Women’s, Forty-Niner, Senior, Silver Senior, Elder Statesmen, Grand Dames, Plainsman Side Match.