I have a 1867 MKII** I set out to make a small game shot load for. CBC 24ga brass cut to 1.95" annealed and sized primed with Fed large pistol magnum primers /60gr FG/ 1/8" 20ga cork wad pushed down snug with a wooden dowel/ equal volume of #8 shot followed by another 1/8" cork 20ga wad snugged in place. Lastly sitting upright white wood glue to seal the case mouth and let sit overnight. Use at own risk. Left the Snider behind the truck seat while I did my morning hunt as I had been seeing grouse along the trail all week prior. Passed one 100 yards from the truck and put my gear away retrieved the Snider and two rds to test. Headshot the chicken at about 30 ft lights out no pellets in the breast.Seems to work.Was attempting to also fireform as .592 slugs won't enter the case necks. Some have suggested I cut the brass to 1.90". It is an iron barrel 3 groove 1863 musket originally I think? No way a .600 ball is going to fit for now anyways.