Initial news stories are often wrong, but it was apparently an old handgun that belonged to his father.
Why “apparently”? The son said that he knew his grandfather’s guns and this was not one of them. And why would his grandfather have had a cannibalized “throw down gun”?
No one in the Foster family ever said that. And if you're going to use a gun to commit suicide, why use an old relic like that very possibly didn't work?
Also, note that the gun was made from parts of at least two other guns - it had two serial numbers on it. Why would his father have possessed such a gun?