Physical bullets not working

i downloaded this physical bullets mod: http://www.garrysmod.org/downloads/?a=view&id=26557

for some reason only one in about 30 shots register. i can see the bullet fly but it rarely makes contact and infilicts damage. the bullet only hits about once every 30 shots. i think it might be confiliciting with this phys addon (not for bullets but general phys) http://www.facepunch.com/showthread.php?t=585848

is that possible?