Off hand I will GUESS it is a .35 Remington. I think that Marlin is the only one left to make one. Not a hard kicking caliber, about like a 30-30. Good for deer and similar sized game. Can be used for larger stuff (elk ect) but will be limited by range even with the new Leverevolution ammo. I agree that it is an accurate caliber with the leverevolution also. Over all I think you will enjoy shooting it.