My guns twitch, I reinstalled Blood 2 twice and the guns twitch constantly. I

This happened to me a few times, but I don't know how I solved it. Try to keep switching through walk and run mode, I think that's how I did it....

Do both of you happen to use Nvidia cards? i just switched to ati and back, one of the upsides to the ati card was better lithtech rendering, including less shaking of the v_weap view.

Actually I've been using ATI only, because all other cards are ugly/buggy in SOME type of way (horrible sprites and fx that look pixely, render distance is very short, etc) but I don't believe the gun shaking was one of them. I actually had it one time when using ATI, and for some reason when I play Gabriella's part of the Nightmare add-on, I get a littl bit of this gun twitching.
Other than that I never really get this problem.

start the game open the console ~ and try maxfps 60
or lower, maybe this will help.