“That particular .45 was used in self-defense, and it probably saved his life on a few occasions and so, he referred to it as his favorite,” she said.

Diane Capone said she didn't know if the gun was used to commit any crimes and said her grandfather, who she called Papa, was never charged with killing anyone.

To me,the operative word is "probably" I agree that it looks like the Family is definitely pumping up the value of this item.
At this point,all we have is uncorroborated 3rd party hearsay.