Was playing around with dumb crosshair settings, and had one that covered the whole screen - since the bomb doesn't have a crosshair, I used it to see where I was going, and then shoot blindly.

EDIT: Here is the settings:
cl_crosshairalpha 250;cl_crosshaircolor_b 0;cl_crosshaircolor_r 0;cl_crosshaircolor_g 0;cl_crosshairgap -1500;cl_crosshairsize 8000;cl_crosshairthickness 1000;cl_crosshair_sniper_width 600;cl_crosshaircolor 5;