I'd really appreciate some advice on how to get past the two automated turrets on adjacent screens on the A2/B2/C2 gantry near the green keycard in chapter 12 (Bridge & a half). Even if I make it past the first I get shot to ribbons by the second as soon as the screen changes. I've tried running, rolling & grenades with no success & the only videos I can find for this chapter just show how to get the signs.
All suggestions gratefully received! Thanks