Welcome to the forum Olpeddler!  You're among friends here...

No Cartouche doesn't detract from a Krag's worth.  Many times, it's simply because the stock was replaced in the field.

I agree with Vic... 4198 is too fast.  For a 180 gr, try 4064 or 4895, and consult a good loading manual for a safe load (Krags are one rifle you don't want to load "HOT")!  In my opinion, 4350 is very slow, and would be way too slow for a 180 grain bullet - you'd have too much powder unburned by the time the bullet leaves the muzzle.