Yes.
Yes. A 3-1/2" chamber will accept 2-3/4" & 3" & 3-1/2 shells
yes
sure - clean it afterward
Yes - this firearm should safely handle today's 3 in. shells
In general, yes, since the 2-3/4 is a lower power shell. If the gun is a semi auto, it may not cycle properly. You didn't identify the gun (there are a lot of model 88's). You will want to clean the chamber at the forcing cone very well after you shoot it to prevent powder buildup when shooting the shorter shells.
The length of the chamber in a 2 3/4 inch chambered shotgun is 2 3/4". The longer 3" shotgun shells will not fit in the chamber, being 1/4" too long. You can shoot 2 3/4" shotgun shells, of the correct gauge, in a 3" chambered shotgun.
DO NOT TRY THIS!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! Injury and/or death can result
The Restless Gun - 1957 A Trial for Jenny May 2-34 was released on: USA: 25 May 1959
Yes, you can.
I have a model 1100 Lt 20 ga. magnum and it will fire the 2&3/4 shells but will not cycle or eject them. Someone told me that the holes in the barrel to let the gas escape are different on the magnum. I bought another barrel for 2&3/4 shells and it cycles them fine with this barrel.
You need to talk to a gunsmith
25% of 34 = 8.5