czbuff
According to the info on this link:
http://en.wikipedia.org/wiki/12_gauge your Model 37 is now Cylinder Bore. In the earlier models of H&R's they used to make a 16ga. in Mod choke. Now, they are all Full Choke.
I inherited a 16ga Sportsman Autoloader from my Uncle. That is a Full Choke. Vintage is around 1947 or 48. I, actually have never seen a Sweet Sixteen in anything other than Full Choke.
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