a metal block in breech-loading firearms that is withdrawn to insert a cartridge and replaced to close the breech before firing

(superlative of `near' or `close') within the shortest distance

(superlative of `near' or `close') within the shortest distance

(superlative of `near' or `close') within the shortest distance

(superlative of `near' or `close') within the shortest distance

(superlative of `near' or `close') within the shortest distance

(superlative of `near' or `close') within the shortest distance

(superlative of `near' or `close') within the shortest distance

(superlative of `near' or `close') within the shortest distance

(superlative of `near' or `close') within the shortest distance