Here’s a photo standing next to 7.62x51.
Primer mark—you can see that the basedisc is still on this round. Lettering is Amt or Amf—part of the last letter is off the collar
Rim stamp #1.
Rim stamp #2—a serial number?
Swedish crowned cannonball mark on the driving band.
The lettering on the projectile will not photograph well—depth of field problems—but it says: m/42C SKF4422 HO.
My limited research has indicated that most projectiles would be solid penetrators, but there are some API.
My question would be—is this projectile solid. or likely to light my cigarettes—all of them, all at once?
There may have been an orange band running around the base about two inches wide, starting at the rim—or this could be discoloration of the brass.
The round looks nice in my display case of random objects, so I hope it’s not dangerous. Any information is appreciated.