Lead shot was pioneered by William Watts of Bristol who adapted his house on Redcliff Way by adding a three story tower and digging a shaft under the house through the caves underneath to achieve the required drop. The process was patented in 1782.
The process was brought above ground through the building of shot towers.
Roundness of manufactured shot produced from the shot tower process is graded by forcing the newly-produced shot to roll accurately down inclined planes; unround shot will naturally roll to the side, for collection. The unround was either re-processed in another attempt to make round shot using the shot tower again, or used for applications which did not require round shot (e.g. split shot).
Larger lead shot comes in three sizes: B, BB, and BBB. Smaller lead shot is available in shot in sizes 7½, 8, and 9, with applications ranging from sporting clays and skeet shooting, to non-waterfowl hunting at progressively shorter distances. The larger bird shot sizes (i.e., 6, 5, 4) are more difficult to obtain in lead, having been banned for waterfowl hunting since the 1970s in the United States, although they are still occasionally seen, and remain legal for uses other than for waterfowl hunting. Older shotguns continue to use lead shot, as firing newer, harder, non-lead shot may damage the shotgun, and firing soft metal substitutes for lead shot may not be economically-viable.
Buckshot is simply lead shot formed to larger diameters. Sizes range in ascending order from size B to size 0000.
Below is a chart with diameters per pellet and weight for idealized lead spheres.
|#0000||Buck||5.51 g (85 gr.)||9.40 mm (0.380")|
|#000||Buck||4.54 g (70 gr.)||9.14 mm (0.360")|
|#00||Buck||3.49 g (53.8 gr.)||8.38 mm (0.330")|
|#0||Buck||3.18 g (49 gr.)||8.13 mm (0.320")|
|#1||Buck||2.62 g (40.5 gr.)||7.62 mm (0.300")|
|#2||Buck||1.91 g (29.4 gr.)||6.86 mm (0.270")|
|#3||Buck||1.52 g (23.4 gr.)||6.35 mm (0.250")|
|#4||Buck||1.34 g (20.7 gr.)||6.09 mm (0.240")|
|#FF||Buck||1.18 g (18.2 gr.)||5.84 mm (0.230")|
|#F (TTT)||Buck||1.05 g (16.2 gr.)||5.59 mm (0.220")|
|#TT||Buck||0.98 g (15.1 gr.)||5.33 mm (0.210")|
|#T||Buck||0.89 g (13.7 gr.)||5.08 mm (0.200")|
|#BBB||0.66 g (10.2 gr.)||4.82 mm (0.190")|
|#BB||0.57 g (8.8 gr.)||4.57 mm (0.180")|
|#B||0.48 g (7.4 gr.)||4.32 mm (0.170")|
There are various places in the world (e.g. Wetlands in Britain) where hunting using lead shot is banned due to the toxic nature of the lead. For these situations, non lead alternatives have been introduced, using materials such as steel, tungsten-nickel-iron, bismuth-tin, and tungsten-polymer.