The rifle was loaded with only a minimum charge of 60gr each time of Pyrodex RS and I was shooting patched round balls. I hadn’t gotten around to increasing charges as I was just testing ball and patch fit. I shot a couple of .495 round balls and a couple .490 round balls with a 10 and 15 thousandths patch. The last shot was a .490 round ball with pillow ticking patch. All patches were lubed with mink oil tallow from track of the wolf. I also swabbed the bore between each shot.
Maybe 6 shots total
When the failure happened the ball went downrange and struck the target about 1-2 feet low at 50yds.
I could immediately tell something was wrong because the wedge key had no tension and after removing the barrel, the hooked breech was driven hard into the tang and was very hard to remove.
I am confident the rifle was loaded correctly the ball was seated firmly against the charge and the rifle was not overcharged.
From looking at the patent breech, where it broke, the metal looks somewhat porous and I believe that it may have been a manufacturing defect /stress cracked/ and/or overtightened when installed.
The first couple pics are of the rifle before I cleaned it the last pic is after cleaning
I am sent it off this morning I requested it be replaced and not repaired, but we will see