Just out of curiosity...  why not jacketed?  The Remington 180gr Core Lokt ammo should work great for the coyotes.  Remember, the Krag was designed for jacketed ammo... and we've been shooting them for more than 100 years, and with little enough wear to still be accurate after said 100 years!  Keep it clean and lubricated, and it should still be shooting great for years to come.