I love my Adler, but the stiff point in the action when opening bugged me. Its about half way through the cycle. I installed the kit from Ignition Custom Engineering that is a spring kit and a roller.
There was not a lot of difference that I could detect.
So I pulled it to bits again and determined the heavy bit was when the lifter gate was being operated. They supplied a new lifter gate spring but I thought it was still way too strong. Seeing I had a spare spring now, I shortened it by 4 coils,. That made a fair bit of difference so trying for better I cut 2 more off. Better still.
I left it at that as it cycles well and still loads flawlessly.
They are all a bit different but may be in another gun those bits may have made more difference but in mine the roller hardly touches the curved flat bar anyway.
They say to put it on the back pin which takes the load on closing. my problem was on opening which loads the front pin. the roller could be put on the front pin but I havnt tried it to see if it makes a difference or not..
Another thing, there is a Utube video of a bloke disassembling the Adler. He removes both action pins. Its not needed . Only remove the front trigger group retaining pin from left to right. Pull down on the front of the lifter a bit and slide the trigger group forward 10mm or so and it pulls out. Its a bit stiff.
Excellent instructions come with the ICE spring kit.