I'm just going to give you the benefit of the doubt and say you're great at aiming. In this case I'll refer you to this thread as to what I think is causing your complaint:
http://tremulous.net/forum/index.php?topic=15224.0The trouble is, if you have a high ping you'll be aiming somewhere other than where you see the enemy whether you have unlagged (behind) or not (in front). Also a problem is how people who are used to this probably won't notice it so much meaning new players will be assumed to be bad at aiming.
So just try joining the lowest ping server you possibly can and you'll have done all you can.#
(and again this is the wrong part of the forums for this)