I had a patent breech blow out right in the front corner of the snail where the bolster meets the barrel. The angle they drilled the flash channel was off just a little, and it was too thin at that spot and blew out. I was testing the rifle for the builder and kept seeing fouling on the barrel and wood just in front of the bolster. I thought it was the nipple blowing downward and put a piece of tape there and shot it. Instead of the fouling being on top of the tape from the nipple, it was under the tape from the leak after I shot.