Help with Backfire

I lost two cams in two engines before I learned the proper break-in procedure and the use of the proper oils. Yes there is fine metal particles throughout the motor and the only way to completely remove it would be to completely tear the motor apart. Short of that I replaced the cam and lifters and installed small magnets throughout the motor and large ones around the oil filter. Fired both motors with the proper break-in oil, used new proper break-in procedure. That was 5k miles ago. Both motors running strong. There is life after loosing a cam.