A firearm projectile has a rear section and a forward section spaced from the rear section. A collapsible spacer is positioned between the forward section and the rear section.

This disclosure relates to self-contained cartridges and launcher systems for discharging or launching payloads to downrange targets, and methods of attenuating or offsetting recoil when activating such cartridges. Examples of payloads that can be deployed with the disclosed launcher apparatus include chemical, biological, pyrotechnic, marker, tracer, signaling, non-lethal, explosive, smoke, and similar payloads.

A cartridge for a firearm, including a projectile, a gas check, a case, a propellant, and a primer configured to ignite the propellant. The propellant is arranged between the gas check and an end surface of the case in which the primer is arranged. The case is crimped against the projectile. The case includes an open end with discrete roll crimps distributed along a circumference of the open end. The case further includes tapered crimps between the roll crimps along the circumference of the open and. The open end alternates between tapered and roll crimps along the entire circumference of the open end. Each of the roll crimps and tapered crimps are crimped to the projectile.

A drone defense ammunition, such as rifle ammunition (e.g., with a caliber of up to 20 mm) or shotgun ammunition (e.g., up to caliber 4), may include projectiles. The ammunition may release the projectiles loosely as a result of an activation occurring with a time delay to firing of the drone defense ammunition.