Originally Posted By: bamboozler
Here's Colonial Arms Choke Chart for 10,12,16,20,28-ga's. and .410 caliber as well as true bore diameters for each:
http://www.colonialarms.com/chokespecs.html


That is a good reference to go by, but some manufacturers of 16 ga, especially L.C. Smith, the bore of pre-1930's guns is .650, changed to .662 after that along with chamber length.

The other thing is, without knowing bore size, choke diameter means nothing. Actually the only way to know what your choke is, is to shoot 5 rounds at a pattern board, choke size means nothing until then they are just numbers.

Last edited by JDW; 03/25/09 06:18 PM.
David