My stock 22A1 came with a 4 pound 8 ounce trigger pull. This gun is very easy to fully disassemble. I found it was easy to bend the trigger spring back, to reduce pressure, and I also bent the sear leaf spring slightly, to reduce pressure. I polished the sear and hammer engagement faces and coated them lightly with a antiseize grease. My trigger pull is now a smooth 3.0 pounds (measured with a Lyman digital trigger pull gauge), with a crisp break. There is about 1/16 of trigger take-up, and about 1/32 inch of over-travel. I do not like the trigger shape, it is too rounded. That is my next job, to make a flatter trigger, without all the hook, especially at the bottom. I will eliminate the over-travel, when I revise the trigger. Over-travel causes me to slightly pull the muzzle, but without over-travel, the muzzle stays rock still. The take-up doesn't bother me, as I pull the trigger to the sear pick up, and then slowly squeeze the trigger to break.
I have seen a video where the person rounded the sear edge, to reduce the trigger pull. The problem I have with that is the stock sear engagement is very shallow with the hammer. Rounding reduces the engagement friction, as there is less surface area to rub against, and would reduce the trigger pull. The issue by rounding the sear face edge is you risk that the sear may not catch the hammer, and end up with a full auto 22. If the impact of the firing pin into the casing does not cause full auto, then the gun is non-functioning. The other problem is you could end up with a hair trigger pull, just a slight trigger movement and the sear releases.
There are five ways to reduce trigger pull:
1. Polish the sear and hammer engagement faces.
2. Reduce the trigger spring tension.
3. Reduce the sear leaf spring tension.
4. Reduce the hammer spring pressure.
5. Round the edge of the sear face.
Number 4 above, could result in light hits. I have stated the problem with #5.
Bob