Btw, in UrT by default F11 is screenshot. In case you used that button for something else:
Code:
bind F11 "play sound/misc/kcaction.wav;screenshotjpeg;ut_echo ^1Screenshot^7 taken."
Or, if you prefer simplicity
Code:
bind F11 "screenshotjpeg"
.
You can usually find you screenshots in the folder where your q3config.cfg is under "screenshots".