Right in front of the chamber in your shotgun barrel is a constriction called the forcing cone. It's there to transition between the larger diameter of the chamber and the bore diameter.
Look at the hundreds of threads on any shotgun forum that talk about shooting 3" magnum shells in 2 3/4" chambers. You'll see that practice generally discouraged in every thread, because the opening crimp of the longer shell as it's fired protrudes into the forcing cone and partially obstructs it as the shot charge goes through.
And yet people are going to say it's OK as a regular practice to blow the whole forward portion of a shotgun shell through that same forcing cone?
All I can say is, I'm not going to unless it is indeed a genuine emergency. Slugs are not that hard to get, nor are they so expensive that I'm going to risk shooting 'rung' shells on a regular basis. I don't consider it safe, any more than I consider shooting 3" shells in 2 3/4" chambers a safe practice. Yes, I know people have done it for many years, people have blown up shotguns in various ways for many years too. I prefer to keep my face and fingers intact as long as possible.
Mindset - Skillset - Toolset. In that order!
Attitude and skill will get you through times of no gear, better than gear will get you through times of no attitude and no skill.