300 WSM failed to cycle while in the field, while hunting. Tore it down, and found my piston corroded somewhat like Steves, and the end of it, at the snap ring, looks like it is flaking off. It does not look right. The inside of the tube has a pit in it as well. At most I have put a 100 rds through it! Is this right? Is it covered under warranty? Is there a recall on this part?