It's enough to go through a anti matter drop ball. However, after penetrating through the ball it tends to slow down a lot, although it can still penetrate enemies after. It can also penetrate through most doors easily.
Dude you could also maybe consider shooting through geometry.. That doesn't exactly ragdoll now does it? I would very much like to know an answer to this question as well. My guess from experience is around 2m but some legit data would be nice