I know the Magnum 1100's that say 3" and 3 1/2" won't reliably cycle a 2 3/4", doesn't matter how clean the gun is...sometimes a Nitro Sporting Clay 2 3/4" would cycle but that's it...

The OP's best option is to try it. All it will do is not cycle...

If it's a gas gun..............clean matters.

Inertia......not so much.


As jeepkid says - Try it !


Follow your break in procedure...............all you can do.