Every gun must be evaluated as to its fitness to fire 2 3/4 shells. However there is a post on 16 ga.com from a article in DGJ, winter 2001 on shooging 2 3/4 shells in 2 1/2 chambers using verious modern loads with pressure recorded. Then same loDs with the forcing cone lengthen, and fily with the chamber lengthen to 2 3/4. You will be enlightened to zee how little the pressure rises. To make things more interesting the also shot 3" shells with no damage. This test only takes in consideration the action of the gun and not the old wooden stock. Worth the read and its about as scientific a study as is available.
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