Just looked at a Damascus steel barreled 1884 10ga gr 2 . It arrived in the mail while I was away at work so when I got home I was like a kid at Christmas opening and having an inspection first thing this morning. To my dismay I noticed what looked like cracks on the right barrel . The heart was pretty heavy as the only reason I bought this shotgun is to shoot Canada geese with it this fall. The seller was telling me that they were scratches however they looked very suspicious. I decided to stop into a Non destructive testing shop and they used a process called Ultraviolet Mag particle testing. They spray an oil based developer on the steel and in a dark room turn on the ultraviolet light. To my glee there was no cracks!
Checking for cracks
Threaded Mode