Cubik2k is the right person for the problem. He was experimented with the damage values and adjusted ammo types (more-less, nothing's perfect), so you should check out his website for more details about it.
thanks lisac2k for promoting my website UInfortunatelly I didn't finish English version of article about damaging calculate in FO2 and FT but only in Polish. However, on this forum there is my old post in article in English about the same problems (about calculating damage in FO2). The alghoritm is in 99,99% right so all interested modders should be satisfaced