I don't carry any tape to the blind, but 12 gauge ammunition can be shot in a 10 gauge gun without tape or inserts. The method is to lay the shells on the extractor and carefully close the gun so that the shell centers in the chamber as the gun is closed, being careful to avoid letting the shell get under the extractor. I have used the 12 in a 10 trick to kill a few ducks. Just last season, I caused a couple of shooting buddies to huddle in the opposite end of a shore blind after I loaded a pair of 12s in my 10 gauge AYA.