You should be aware that there are at least two trigger group designs for this rifle.
Mine, also suffered from inconsistency, and creep. I took it apart, cleaned it, and polished as many surfaces as possible. it's amazing how much that improved the consistency.
Grinding the sear is how the trigger is adjusted. Thats a one way process. Go to far, and you are on a parts hunt to fix a dangerous rifle.
It can be ground without disassembly with a dremel tool.
BE careful!