Nitro Specials are solid utility grade guns and the chambers no doubt started out 2 9/16" and should be measured. You'll find lots of good information on the 16ga Society site, including appropriate shells for your gun
http://www.16ga.com/forum/
The gun is probably well past a good check and clean. Let us know where you're from and we might be able to recomend a doublegun smith near you.

Last edited by revdocdrew; 01/02/08 11:29 PM.
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