Abstract: A cartridge for firearms includes a bullet connected to a casing. The casing includes a cylindrical wall that extends to an end member opposite the bullet, a hollow interior formed by the wall and the end member, means for receiving a priming composition, and means for compressing the priming composition with a firing pin engaging the end member. Propellant is placed in the hollow interior and ignited by the compressed priming composition.

Abstract: A removable ammunition magazine has a body with a side wall. The body defines a passage sized to hold ammunition and an opening intersecting the passage. The opening is sized to pass ammunition therethrough and includes a notch in the side wall. A follower is moveably positioned within the passage for positioning beneath ammunition placed within the passage. A magazine spring yieldingly urges the follower toward the opening. A bolt catch actuator is coupled to the follower. The actuator includes an actuation finger carried with the follower and an activation spring in contact with the finger. The spring projects the finger through the notch when the follower is aligned with the notch. A fire arm with a magazine having a bolt catch actuation finger movable relative to the follower is also disclosed.