This happen recently at a gun range that I use frequently. The range officer gave me permission to share the photos. This happened with a new shooter and his new, very expensive custom 1911. The shooter was using Parabellum Research (PBR) ammunition when he had a squib round and fired the next round into the squib. Luckily the frame and slide held up well and did not appear to be damaged. Only the barrel had been damaged. The manufacturer of the ammunition is taking care of the firearm owner. The range advised it has been having problems with this particular ammunition manufacturer.
It is important as a shooter to quickly identify when you have had a squib round, to avoid firing then next round into it and blowing your barrel and firearm up. If you have the money to buy a custom built very expensive firearm, (no matter what it is), don’t shoot low quality / cheap ammunition through it to save a few cents. You had the money to buy the firearm so don’t get cheap on the ammo. While this can happen with any ammunition, if you buy known quality factory or premium factor ammunition, this will lessen the chances of having a squib or catastrophic failure.