Mike A.
My cousin has a Stevens in 44XL, and I gave him some 7x57R cases for his loads. Cut to length, they worked well, 8x57R would work also. I had some shot loads based on 30-40 cases that worked OK, but were smaller in diameter. I think he used #8 shot, but don't remember powder load. He closed them off with a card wad and waterglass. You could also use Titebond.
Mike