A very unscientific way of testing would be to put the shotgun in a gun vise or sand bag it into position with a pile of sandbags, tie a string to the trigger, load the gun, then fire it with the string while standing a good distance away from it, or maybe from behind a solid wall or vehicle. Use the heaviest loads you can find that will fit the shotgun, look for any problems like blown primers, split bases, hard extraction etc. If you don't have any problems, and have put enough rounds through it to feel comfortable with it, you should be ok. Also check for positive feeding.

Disassemble it afterward to check for cracks, peening, or other damage.



I've done this with a number of guns- some of them over 100 years old to sort of 'proof' them myself to check for headspace or weak metal problems on rifles. I still have all of my fingers and other appendages.