dna and prints can only be taken off the casings, if he left any (revolvers are your friend). you can't just get it off the sidewalk where hundreds of other people walked, and he didn't even touch it. be probably chose to not wear gloves to have good articulation of the slide. but take care to not touch shit. a jewelry robber was caught because he pointed to the glass of what he wanted the store clerk to take out. the cameras showed the exact spot he pointed to and the witness can be asked if they touched anything too. a nice little print was lifted from that spot which got him a nice little warrant. wouldn't want a based "criminal" to get caught this way.
United States