As others have stated, the 2" guns became popular in the 1930s. They were built for a niche market to compete with other lightweight 12s (e.g., the Churchill XXV). The proof load for these guns changed with ammunition. The manufacturers and proof houses argued back and forth on the proof. Some guns are proved at 7/8 oz and others for a 1oz proof. It may have been a solution looking for the problem, but I won't sell mine.
RST makes different 2" loads for them. A gun that weighs less than a 20 and hits like a 12. What else could you want? :-)
Ken
