Problems with the SSS trigger.. pull weight doesn't stay set

I installed the SSS trigger last year. Since then it felt like the pull was getting heavier. Recently I picked up a trigger gauge and sure enough.. the pull weight was at 4.5 lbs.

I got it adjusted down to a 1.5 lbs. After several dry fire attempts it stayed at 1.5lbs. This weekend i put 40 rounds through that rifle.. and sure enough the trigger felt like it was getting heavier. Measured when I got home and its back at 4.5 lbs. It's not consistent either. A couple of dry fires come in at 2.5 lbs but most are over 4.

Talk about frustrating.. does anyone have any suggestions?

Thanks

Reset it, but add a tiny drop of nail polish on each screw. It will help keep them from adjusting on you under recoil.

Dirty triggers can cause issues as well. Use lighter fluid to flush it out and take LoneWolf's advice