Have you measured the chamber in the barrel of these guns? Wingmasters or 1100s will have "Magnum" stamped on their receivers if they are made for 3" shells. Even though the magazine will hold 3" or 3.5" shells, when the shell fires, the crimp opens and the crimp is restricting the barrel in the shorter 2 3/4" chamber: Imagine having a chunk of ice frozen inside the barrel - these are well made shotguns, but eventually something will give. It wasn't intended to handle the heavier shells either and you will be stressing the locking mechanism and action beyond what it was intended for.
The replacement barrel that I mentioned is a new production Wingmaster 20" smoothbore rifle-sighted barrel. It is specifically stamped 2-3/4" AND 3". Oddly, the packaging indicates it is 2-3/4", 3", and 3-1/2". Keep in mind that they use the same clam-shell plastic packaging for all their barrels, so maybe they are just covering their butts as far as printing costs. I have seen anecdotal evidence to suggest that it may even be reamed out at the factory to 3-1/2" just to keep the assembly line simple. But I have not confirmed that yet. Regardless, the replacement barrel I have is definitely marked 3", and I have every confidence that it is at least capable of doing this. This does not apply to the original 28" 2-3/4" barrel that I removed and placed in the corner.





















































