Gentlemen,
I suggest looking at the "Big Bore" BPCR Silhouette shoots. BPCR Silhouette shooting is a great team sport as well as extremely challenging for the shooter. Some up coming western matches include the Oregon Regional, Idaho State, Montana State, NRA Nationals, Montana Regionals: all have a minimum of 4 days of intense but very friendly competition.
Check-out the competition forums for details.
But - that's not at all what was being discussed. The Libby shoot was GREAT! Involved "safari" type rifles from 9.3x62 and 375 H&H and up, at modest range, often moving targets. A few guys with 45-70's were "grandfathered" in. Charge-stopping stuff. Incredibly fun and unique.
I was really disappointed to see the Libby shoot discontinued. Another could be set up, but it takes a lot of time, dedication, and some sort of shooting range...
Regards, Guy