I have the lever action bug and after seeing all the cheap Marlins in 30-30 I wonder if getting on and improving it would be worth the effort. From data I have seen published it is only capable of 2,600 fps. with 130 gr. bullets. I have heard it is almost able to hit .300 Savage velocity but havn't seen the load data to back it up. There are lots of used Marlin barrels around so it would be simple to swap back if necessary