Greener Crossbolt - A tapered round bar, operated by the toplever of a shotgun, passing transversely behind the standing breech of a side-by-side gun and through a matching hole in a rib extension; to strengthen the lock-up.

Greener Crossbolt - A slightly-tapered round bar, operated by the opening lever of a break-open side-by-side gun, passing transversely through the standing breech and a matching hole in a rib extension; to strengthen the lock-up.

Scott's crossbolt operates similarly, but is square in cross-section.

A Kersten Lock operates on the same mechanical principle, but is more suitable for over/under or single shot guns.





The above is from http://www.hallowellco.com/abbrevia.htm#G

Pete

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