The Marlin in 45/70 is an excellent tool. The problem is with the standard factory ammo that is available.
If you were to have a friend use the Sierra Rifle reloading book as a guide and add a simple scope to the Marlin, I think that you would get quite a surprise. derf

Hate to rub it in , Will, but you missed an opportunity to pick up what should prove to be a pretty good factory load for elk in 6.5x55. An outfit in Roseburg, Oregon called Cascade Ammunition had some Federal Premium Ammo loaded with Trophy Bonded Bear Claw bullets in the 140 gr weight on closeout for just $11 per box. Sorry to say, I got the last 4 boxes they had. If my son ever decides to try for an elk, I think he now has some capable ammo for the task. Me, I will probably use the Nosler 140 gr Accubond in my .270WSM. But the hot deal on the Federal ammo saved me from having to buy some 6.5 caliber Nosler 140 gr partitions. I also handload, and believe that the 6.5x55 is an excellent cartridge for most big game at reasonable ranges.