Has anyone tried cut shells with birdshot. ?
Where you score/cut the shell about halfway down so the shell flies with the shot and keeps the shot together until impact.
Long, long time ago I tried that type of load, we used to call it a "Quincy" load. It never hurt the barrel of my shotgun, but then again it's cylinder bore (30" full cut down to 18 1/2")
When we fired it into a gallon jug the water seemed to vaporize and the jug was blown flat. As I recall, only a small percentage of the #8 shot actually penetrated the back of the jug--very, very impressive hydrostatic shock effect.
I also fired one of these homemade loads into a 6" kiawe branch from about 10 yards--there was a 12 gauge hole blown completely through the branch--cool!
After that I really didn't have much use for them so I quit making them.
BTW, I would advise you not to carry such loads into a hunting area--it not strictly forbidden but do you want to go through the hassle and expense of fighting the DLNR in court should they find such loads on you in a hunting area?