That's what I was thinking, but I'm starting to find examples of guys resizing 7.62 LC brass to 6.5 CM. On a side note, PWS makes an MK220 (long-stroke piston AR-10) in 6.5 CM. That's my 2nd favorite AR10.
Here's an intriguing example:
http://www.65creedmoor.com/index.php?topic=1996.0
"I've...