I've shot through the Owens with a Honey Badger and AP.. I mean, I was trying to get the guy running in and managed to kill some guy running across the tracks toward it on the other side lol totally random stray fire.
It doesn't at all sound like he was attempting to shoot original poster, especially considering the guy that dropped him was using a chainsaw lol just sounds like a random stray fire wall-bang.. happens a lot honestly, there are times you'll spawn in and take a few steps and bullets will come ripping through the building, which you figured you were save running behind, and randomly nail you.. I don't know how many total sh*t shot kills I've gotten trying to catch some guy running into a building and murdering his buddy clean on the other side of it...
Same theory as shooting up in the air randomly and the bullet drops and kills some dude a couple miles down the road.. just through a building.
OP, he wasn't actually aiming for you as though he knew you were there, he was just shooting and managed to actually tag you. No harm, no foul, and he probably went "Oh, holy crap, I got someone!" and was just as shocked as you were.