Greetings:  One source of commercial ammo that seems to be usually available is Bitterroot Valley.  Several internet retailers sell it.  Bitterroot makes good quality 30-40 ammo in 3 bullet weights.  However, there is a problem with ALL commercial ammo that you may not know about yet.  Some unaltered Krags will only feed round nosed bullets unless you do them one at a time, but round nosed ammo does not seem to be easily available unless you reload.  You might buy one box of commercial ammo with pointed bullets and see if they feed.

I've had good results (feeding and accuracy) with this ammo:
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