Not sure If there is any collector value. Same cartridge as the 6MM Remington that is still being offered. Great round, and in my opinion superior to the slightly less powerful 243 Winchester that became more popular because of different marketing stratagy. While Remington sold it a strictly a varment round, Winchester used a faster twist in the rifling that stabalized heavier bullets better to make the 243 a dual purpose rifle.
http://www.theintermountain.com/page...g-History.html