Thanks Pete for the Photo.
BK42261 There are several reasons you might want to try the Magtech brass shells, or 'makeshift' centerfires that are a close fit. Hull life for .410's is bad. In my experience of loading them back to the mid 70's, Remington plastic has a nice memory to the crimp, helping to get good crimps on your reloads, but use a brass flashed steel head. After two reloads without a pass through a resizer, the shells will no longer chamber even in the only chamber they've ever been fired in. Winchester compression formed has been replaced by "HS". The Win CF's had a brass head that would go 8 loads easy but the crimp would 'shoot flat' and be barely perceptible even on the first firing from a factory load. It's hard to get a good crimp on the reloads, and a few (like 3 to 10 in 25) will have a botched crimp that may be 3 or 4 folds instead of 6. These then will quickly split in a firing or so, and you lose cases due to ruined case mouths. Sometime 10 years or more back, Federal cheapened their 3 in hulls and went to a roll crimp. Doing a folded crimp on a fired roll is easy with paper shells, and VERY challenging on plastic. In short, no 410 plastic case gives case life or loading ease that you take for granted in a 20 or 12.
Paper case 410's burn through just above the brass in about 2 or 3 reloads usually. Reload a paper case with pinhole burns at the brass top and the head either breaks off on extraction or the tube goes down the barrel when fired. (Plastic cases also can fail by burn through, but bad case mouths or loose primer pockets often fail the case before this happens).
Also, brass cases can give you back some internal volume to get back to 3/4 oz shot, or use a different primer style you may have more of (such as a rifle or pistol primer instead of a shotshell primer). Finally, they may exist when you no longer have a paper or plastic hull of any kind available (but, I'd argue, standard hulls will exist long after you can find a .303 .30-40 .444 or some European Metric to make a 410 case from!)