The early production 1897's, of which yours is one, were chambered in 2 9/16ths. They weren't intended for use with 2 3/4" shells. Having said that, the guns are solidly built and I have never heard of a single failure from using 2 3/4" shells*. *Winchester 1897s only - not talking about clone crap.
Still, using any other than 2 1/2" does put more strain on the barrel assembly. Continued use eventually causes looseness in the take down mechanism. Other than myself, I don't know a single soul who uses only 2 1/2" shells in their '97s (including my Dad, before he handed a 16 ga down to me). In my case, it's not so much concern for the gun that motivates me, but a desire to use traditional shells with felt wads that make full use of the gun's choke, to use loads balanced to the weight of the gun, and to enjoy reduced recoil (by not constricting the forcing cone with the crimp or using heavy loads).
I've taken steps to acquire sequential adjustment collars, so I and my progeny won't ever have to wish we could get the parts to keep the old girls shooting. By my calculations, it should take at least 500 years to go through the whole range of adjustment offered by the design. I was conservative in my estimates. The real number is probably closer to 750 years and using the correct shells would push that to a millennium. Obviously, nobody feels compelled to worry about making their guns last that long. But, reduced recoil and better patterns are worth the effort.