If you manage to get out of bounds, you can sometimes find the bot that's shooting. I believe the game has to populate two teams in order for a "round" to start, even in the practice range. So it loads a bot for the enemy team that just hangs out in the abyss behind the walls and occasionally shoots their gun (since I imagine the anti-AFK also works on bots).

I've never gotten out of bounds to test it, myself, but I wonder if the bot has a name in the kill feed if you kill it or it kills you.