I used this brand of lump today and was wondering if someone else has encountered what I did. I started a chimney full of lump and after heating for 5 minutes or so it started popping. I hear a little popping is normal but this was no little pop. It sounded like gunshots going off. It was enough of a pop to shake the chimney and the last of the pops blew out a crater in my driveway. I was using the minion method and it never did it in the firebox only in the chimney that first time.