01 n. A groove in any cylinder; specif., a groove around the cylinder of an elongated bullet for small arms to contain a lubricant, or around the…
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A groove in any cylinder; specif., a groove around the cylinder of an elongated bullet for small arms to contain a lubricant, or around the rotating band of a gun projectile to lessen the resistance offered to the rifling. Also, a groove around the base of a cartridge, where the extractor takes hold.(Mil.)