This is an easy fix for a gritty and/or hitchy trigger.

Cut a 1/2" wide strip 4" long of 1,000-grit wet/dry sandpaper. Roll it up tight on the 1/2" dimension--smaller than the striker block channel. Insert into the hole and let it expand. Move it in & not quite out about 6-10x, turning it as you go. The paper will be stiffer if dry rather than wet with water or oil.

Repeat the same thing in the striker channel where the striker block channel intersects. There is often a burr here because of machining. You may need a slightly bigger piece of paper. It wears quickly, so keep using new pieces.

Polish the striker block lightly, both the sides and the bottom rim that engages the trigger bar.

Polish the edges of the trigger bar that engage the striker block and the sear.

Clean the sanded areas thoroughly with pressurized spray cleaner. Dry. Lightly lubricate the striker block channel and striker block, but not the striker channel or striker. I put a thin dab of grease on the engagement surfaces of the trigger bar. It stays in place better than oil.

Your trigger pull will be smoother and a little lighter unless the channels were already smoothed from 1,000+ rounds fired or having had this same procedure slready performed.

Good luck. It is even easier to do than it sounds.