Dude, if your trigger is letting off when you release the safety, something is WRONG! Did you change the sear engagement? Sounds like it. That trigger is currently UNSAFE. Take it to a gunsmith and get it adjusted now.
FWIW, I have one 700 in .308 with the X-Mark trigger and (after I adjusted it properly) it is an excellent hunting trigger. Every bit as good as the older style 700 triggers for hunting.
