Volume 37, Issue 4 (July 1992)
Ballistic Characteristics of Shot Shell Buffer
Many modern buckshot and larger diameter bird shot shotgun shells currently contain granulated plastic shot buffer. The presence of granulated buffer at a shooting scene provides valuable and immediate evidence of the general type of weapon and ammunition used.
The ballistic characteristics of the buffer however are not commonly known but could be helpful in determining range of fire. Using felt targets and various types of 12 gauge shotguns and ammunition (2¾ in. shells), we discovered adherent buffer on the targets up to 20 ft (6.1 m) from the muzzle. Surprisingly, buffer would penetrate light cotton cloth (white T-shirt) at ranges up to or nearly up to the maximum range of adherent buffer on the plain felt targets.
The diameter of buffer spread was up to 9 to 10 times that of the pellet spread. The buffer distribution diameter peaked at 3.3 ft (1.0 m) between the 8 to 10 ft (2.4 to 3.1 m) range of fire and remained roughly constant at 28 in. (.7 m) throughout the buffer adherence range beyond 10 ft. Along the ground buffer was demonstrated up to 30 ft (9.2 m) from the muzzle but was concentrated in the 12 to 22 ft (3.7 to 6.7 m) range. Buffer clearly could be deposited on objects not struck by pellets. The presence of buffer, but not its distribution diameter, was helpful in determining range of fire.