Often the 6,5x55 from factory are made on a .30-06 length action. If one wants to settle with 120-130grain bullets a .308win length action is just fine.

From overhere perspective the 6,5x55 is by far the best taking accuracy and availability in ammunition. There might some other special 6,5mm that does 0,5% better but it ain`t worth the flip.

In regards to 6,5s..I went shooting a kurz mauser Model M in 6,5x54 here last weekend. Lovely little thing for the truly dedicated roedeer hunter who insist using a boltaction rifle.(the gun was once mine).