Something like that...Don't you mean it's not his, it's his friend's and he's just holding it for him? LOL
I have seen many a gun picked up by police because it shows to be stolen in NCIC. Most of the people who have them walk away if they have a decent explanation of how they got it or if there has been an extended period of time since it was reported stolen and there is no affirmative link between the guy who you are taking it from and the theft.
That having been said, if a gun is stolen at 8 am and you are found with it at noon, you are probably screwed.
If it was stolen in 1984 and you are found with it today...probably safe.