200 yards at the Alliance Rifle Club range in Malvern, Ohio.
I had read about pre-WWII long range revolver shooting at a club in Louisville, KY, so when a friend was moving to Seattle, so we had a farewell revolver shoot.
We put some full sized man targets on the target frames and shot at them with a 6" K-38, a 6" Model 14, and a 6" M&P respectively.
I had done this kind of shooting in college with my Series 70 Colt, and was able to easily hit an oil drum on a sand spit in front of a pond in some clay pits. I estimate that the range was somewhere around one hundred fifty yards. I was using VERY mild bullseye handloads with 200gr. LSWCs, and either Unique or Bullseye. It couldn't have been much more than 3.8gr. of Bullseye. I shot from the recumbent position.
Shooting the Model 14 20+ years later, I was using Winchester White Box 140gr. .38 Special FMJs, which are about equivalent to .38 Long Colt. I tried to find 158gr. LRN, but couldn't find any ANYWHERE here in time for the trip.
Once I found the range and a consistent aiming point, I was able to keep most of my shots on the paper.