Willie has it right, this isn't the same thing as loaning out your car where the law is concerned.
If he had STOLEN the firearms then he'd be in possession. But knowingly and willfully leaving them to his father is enough for the law. The felony just seals it.
Sig 1911 Traditional reverse two tone, Sig p226 .40, Sig 556 Swat patrol, Baby Eagle/jerico steel .45