the Remington X-Mark Pro trigger can be adjusted down to 3# minimum and still test safe. I really don't know what these others are doing wrong, but I have several Timney triggers, an Accutrigger, and the X-Mark Pro. I have no reason to change out the X-Mark, it breaks crisp, clean, and consistant at 3# against my digital pull scale. If you want to go below 3# then you may need to change it out.
anyway, to adjust the trigger, here is a great link to the correct info you need. Adjusting the Remington 700 Trigger
if your not sure you want to tackle the whole setup procedure, just adjust the front lower trigger pull screw. adjusting just this one screw is the easiest and quickest to just lower trigger pull weight.
One note: later X-Mark tiggers I've seen have excessive amounts of loctite on the sear screw that makes it next to impossible to perform the complete adjustment. (I guess Remington's trying to keep us out of there). lowering the trigger pull adjustment (front lower screw) will get you down to 3#. that's the pull weight I have set for my hunting rifles and does quite well on the bench at that pull weight . only my target bench guns have triggers set below this, generally in the 2# range or slightly less.
Whatever you choose to do Always test the finished product extensively before loading the firearm!