That's been debunked. Guy dumped over hundreds of hours. It's dependent on the number of stratagems used, and cardinal direction. And some other variables.
I once fired a shot from a railgun at the exact same time that it blew up on me. Reason I know is because I saw the bullet trail, and the hulk I was targeting got a hotspot on his armor. Strangely, the hulk didn’t seem to notice or react to being shot.
You have enough time to run underneath them btw. If they are spewing bile they will be attacked locked, and will transfer into ground stomp mode. You can use this tactic to run back and forth underneath.
I love how it shows the round skipping off the armor of the armless berserker but it still dies. Enough power for penetration just not enough to break through all the way.