I'd say
around 25 yards.
How often did you encounter a nice one just outside of thisrange [align=right][/align]
Often enough. Last year, I had the biggest deer I have ever seen in the woods (roughly 160 class) walk by at 30-35 yards. I then had him in the wide open broadside working a scrape at 40 yards. [:@]
He was walking directly at my partner though, unfortunately, he crossed just the other side of the ridge, and my friend heard him, but didn't see him.