My best load thus far for the newer Krag have been with 308284 and 14.5-15.5 grains of 4227 at about 1,400 to 1,500 fps. 9 gr of Unique will group the Squibb bullet well at 1,350 fps, and the 308259- the bore corking Hudson bullet, likes 16 grains of #2400 at 1,500 fps. Surprisingly, the 308243 shoots very well with fourteen grains of 4227, but only weighs 165 grains.All the above bullets were cast of common WW plus 7-8% 95/5 solder, and sized .311". They come out plenty hard. My standard load for the Redfield sighted Krag has been 22 gr. of 4198 at around 1,700 fps (311291) sized .311" cast of straight WW and seated to give an OAL cartridge length of 3.085". I've killed a lot of small game with this load, including one tree squirrel at 200 yards.
I'm a "one rifle-one load" sort of guy, but haven't developed the load for the newer Krag yet. I can wait.