Re: "Tightening" shotgun action
Loose breech, my limited experience was , 1930s, my GFather's 1880s Belgian damascus double 12 ga loose mostly in the latch. Being a resourceful kid with a 'scientific' mind, I carefully dinged the ledge of the latching lug on the bottom of the barrel to upset a bit of material and take up slack. Made it as tight as new. Closing tighter pulled the 'doll's head' deeper into the receiver, good job all around.
The gun, GFather bought used in 1886, in So. Texas, accounted for quite few deer in black powder days. Me, smokeless, fired it hundreds of rounds, jack rabbits, cottontails, ducks, snakes, whatever crawled, ran or flew.
As above suggested, now a wall hanger for my Son-in-law.