I wanted some HD loads for my 4.5lb pump gun with aluminum action and barrel. I took some Fiocchi 20ga 3/4oz trainer loads and dumped #7,5 shot replacing it with either #4bk or #1bk. I used some plastic filler to eliminate the void space. I do not do it anymore or use the shells because knowledgeable member of the forum told me it was not safe thing to do. I would not describe what I did as shot shell reloading. Now I have fine Remington 16ga auto so I can just use Federal #1bk loads.