The very first group ever shot in the "Threes", Frank Weber shot this 3.960"er back in the Banquet Shoot for 1993. On November 14, 1993 this group became the new World's record for 1000 yard benchrest. The group it bested was only a few thousanths bigger. Bob Frey shot that earlier in the year at 4.076.
Frank to this day also is the only person ever to hold the 1000 yard record twice. Back in 1970, Frank also held the record at 8.468" albeit if only for two weeks. It was broken the following match. Still, 35 years later, 8.5 ends up in the 6 match agg of nearly everyone.
The thing I find remarkable about this particular group is that it's one of the very few with less vertical than windage. Immagine what it might have looked like had it been a nicer day.