The Gualandi DGS slugs might work well. The Canadian load is 496gr. at 1,610fps. Bit pointy, but good full diameter ring.
https://www.google.com/search?client=fir...ld=cid:1b06a8ef,vid:TCxA2IYneqM,st:0
The Qualandi's run about 2" for 5 shots at 30yards from my 24" Mossberg rifled tube & open sights, same as the Winchester 3" 1 ounce Fosters at 1,750fps.