Not if you want to continue living.
Yes
Yes, shorter shells are no problem.
Your question needs some work- as written, has no meaning. A shotgun marked 3 inch can shoot 2 3/4 inch shells, or 3 inch. A gun marked 2 3/4 inch can only shoot those- no 3 inch shells.
If a shot has a 3inch chamber it will also shoot - 2 3/4 inch shells..
yes.
All day long. Any shotgun can handle shorter shells than it is chambered for as long as they are the same gauge.
1926 IS THE YEAR THAT WINCHESTER WENT TO STANDARDIZED 2-3/4" LENGTHS ON THEIR 16 AND 20 GAUGE SHELLS.
yes
Yes it does I have one.
Per federal regulations, it can only hold a maximum of three shells (2 in the magazine tube + 1 in the chamber).
Yes but not the other way around .You can not use 3" shells in a 2 3/4 chambered gun.
Yes I own one but you must turn the spring around.