Cast bullet, without a doubt. Three trips to Africa, two with a 45-110 and one with a 45-70 using both round nosed and flat nosed cast bullets gave quick kills and complete pass through penetration. 1250 to 1300 fps is more than enough velocity. Check out Black powder zebra kill on youtube. That was a 480 grain flatnosed bullet out of a 45-70 Shiloh Sharps at 1244 fps.
Using the 45 caliber cast lead bullet In North America, I have taken a dozen bison and three elk and I don't know how many deer and hogs with the lead cast bullet, and have never recovered a bullet or lost an animal. My friends and I have settled on the 480 to 500 grain flatnosed cast bullet at 1250 fps as the most reliable killer, as it gives complete pass through on bison, moose, elk, and big hogs.
If you cast your own bullets, the Lyman 457121 cast of 50/50 wheel weights and lead, or just straight wheel weights is THE bullet for your Marlin Cowboy. I run it at 1300 fps out of mine, and recoil is not a problem. This load kicks about like my 30-06 with a factory 180 grain load and feeds through the Marlin like it is greased. Your Marlin Cowboy loaded with the 457121 is the Real Deal and with a ladder barrel sight will reach a lot farther than you would believe. It is also a pure HAMMER at this velocity with this bullet. I frankly feel sorry for anybody that uses anything else, this works so well on so many levels.
Last edited by sharpsguy; 06/19/18.
