If it hasn't blown up in more than a hundred years, it is not likely to blow up tomorrow with moderate handloads.
  Mike 
 I'm afraid that doesn't really hold water. Each year there are 100+ year old guns that blow up. Some are carelessness in loading by their owners. But others are unexplained, and usually attributed to the age of the action, and the metal finally saying enough. Every low serial number '03 that ever blew up didn't do so when it was first sporterized. There's enough recorded cases over the decades since they've been pointed out as potential problems to show that this can still happen over 100 years later.