The .410 bore is one of the smallest caliber of shotgun shell commonly available (along with the 9mm Flobert rimfire cartridge, and the less common .22 rimfire shot shell). A .410 bore shotgun loaded with shot shells is well suited for small game hunting and pest control. The .410 started off in the UK as a garden gun along with the .360 and the No. 3 bore (9mm) rimfire, No. 2 bore (7mm) rimfire, and No. 1 bore (6mm) rimfire. .410 shells have similar base dimensions to the .45 Colt cartridge, allowing many single-shot firearms, as well as some derringers chambered in that caliber, to fire .410 shot shells without any modifications.
