Hunting rifle.
It has a heavy barrel and the 700 adl action
Some reviews didnt care much for the trigger (which if memory serves me right, you dont either)
It's not hard to do but to do it correctly take some attention to detail. You can end up with a trigger with too much creep or dangerously light. Many people do it themselves but few do it the right way.
I'd suggest taking it to a professional but here is the proper process if you think you are qualified.
Check to make sure the chamber is empty before anything else. You'll want to gather some penetrating oil, an Allen wrench set, precision screwdriver, and Elmer's glue. I also recommend a trigger scale to make things as accurate and safe as possible.
First thing, remove your barreled action from the stock. Use a 5/32" Allen/hex wrench. Remove the front screw three-fourths of the way. Then remove the rear screw all the way. Make sure you remember that the long screw goes in the tang area, and the short one goes in front of the receiver.
After the barreled action is out, use a penetrating oil to soak the three trigger screws. If the trigger has never been touched before, there will be a sealant on the screws. Simply scrape it off before applying the oil. Let the oil soak 10 minutes or so. You'll then want to turn the screws in and out three or four times so that you make sure there is no binding.
You will then want to back out all three trigger screws two or three turns, careful not to back them out so far the springs fall out of place. You simply want to take the tension off the internal springs. You will then work the bolt. Slowly start turning the sear engagement screw, located on the back side of the trigger, in until the sear releases and the firing pin drops. Back it out exactly one half a turn.
Next, the over-travel will need adjusted. This screw is located on the top front of the trigger above the pull-weight screw. Do not recock the rifle. You will want to turn it inward until you feel resistance. When properly adjusted, the slop will be taken out of the trigger and it will move back and forth very little. Do not over tighten. Though the travel will be reduced, the pull weight will not be able to be adjusted. If not turned in enough, the pull can be adjusted lighter, but it will be very sloppy and unpredictable.
You are now ready to recock the gun. Use the trigger scale and see how heavy the weight is and if its to your liking. If not you will have to adjust the pull-weight screw, below the over-travel screw. Inward increases the weight and outward lightens it. Trial and error will get it to the point that is to your liking. As soon as its to your liking, you will want to try it approximately 20 times. Work the bolt quickly as if you were going to in the field. This will show you if the sear will accidentally release or not. This could be disastrous. You'll want to make sure the pull-weight is consistent and without slop or excessive over/under-travel. You'll shoot better groups with a 3 lb trigger that is consistent rather than a 1 lb trigger that isn't.
After you are convinced everything is set where it should be, take the Elmer's glue and put a few drops over the screws. I use Elmer's because it will stop them from creeping out of adjustment over time but will be easy to remove if you so wish to change your weight for a different application later on. Finger nail polish and lock-tight compounds are more difficult to remove, but effective. Allow the glue to dry fifteen minutes.
You'll then want to put the thing back together. Slide the barreled action back into the stock. Put in the front (short) screw first and turn in half way. Then put in the tang screw and turn in all the way tightly. Then turn the front screw the rest of the way. If you have an HS stock, you'll want to put them in 65 in-lbs. If you have a wooden stock, many have different ideas on how tight to turn them, but that is not a discussion for here and now. After all is tight, check the trigger pull for safety against ADs. Slam the butt stock of the cocked rifle down on the floor 10 times or so to make sure it won't go off.