I have ground enough strain screws in my time that I can feel when I have it at just the right length (scale not necessary). After grinding them I also contour the tip to look Factory - just because. It gives me a nice light and smooth feel with 100% reliability with any primers out there. Yea, once in a rare while I might go a bit too far - so I'll toss that screw and start with a new one. They are cheap enough and it doesn't happen very often so I don't mind. They all get fully tightened.

I also have different guns for different purposes. I have my Competition Guns, Target Guns, Combat Guns, Hunting Guns etc. and they are adjusted specifically for their intended purpose. I NEVER adjust the original - I put that in a little plastic envelope inside the original box with a note that specifies what it is. I also replace any modified screw with the original on the rare occasion I sell a gun. I NEVER modify an original part on any gun - I always use new ones!

This might be different than some people do - but I can only comment on what I do and what has worked for me. YMMV.