Chokebore

• (n.) In a shotgun, a bore which is tapered to a slightly smaller diameter at a short distance (usually 2/ to 3 inches) to the rear of the muzzle, in order to prevent the rapid dispersion of the shot. • (v. t.) To provide with a chokebore. • (n.) A shotgun that is made with such a bore.
Found on http://thinkexist.com/dictionary/meaning/chokebore/

Chokebore

Choke'bore` noun 1. In a shotgun, a bore which is tapered to a slightly smaller diameter at a short distance (usually 2½ to 3 inches) to the rear of the muzzle, in order to prevent the rapid dispersion of the shot. 2. A shotgun that is made with such a bore.
Found on http://www.encyclo.co.uk/webster/C/70
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