Brokennock: get one of the stainless steel 6" pocket rulers that are available at most any hardware store. Remove the barrels from the gun and point them toward a good light while sliding the ruler along the chamber wall and observing when the end reaches the ring that you can see. That should give you the chamber length. Anther way is to use a set of old fashioned spring leg inside calipers. Adjust the calipers until you can just feel them slide along the inside of the chamber. When the tips reach the beginning of the forcing cone, you wil feel the abrupt change of angle and can make a pencil mark on the caliper leg to measure from the tip. Sometimes you can make more accurate measurements with the above two methods than you can with plug gauges. The accuracy of a plug gauge depends on its being made exactly to spec, and the chamber being bored exactly to spec, but if the chamber is undersize only 0.001", because of the taper, the plug gauge will read 1/4" short.
Last edited by Tom Martin; 12/23/16 09:31 PM.
