This article covers a subject that has been deemed non-canon by either the author or the Alien vs. Predator licensees, and thus should not be taken as a part of the "real" Alien vs. Predator universe.
"High-explosive composition B15 fragmentation shells; When fired, the shell's fuse is activated, creating a short delay before detonation."
The B15 Timed Explosive Shell is a cartridge filled with a high-explosive B15 fragmentation projectile, when fired the timed fused is activated allowing the projectile to bounce before detonation.
Trivia[]
The B15 Timed Explosive is unlocked by default with the M37A2 Pump Shotgun.