Nice work on the sporter and interesting alteration making a new lug. A major flaw of the old Krag were the delicate stocks which you seemed to have fixed.
I hesitated before posting the following for the last couple of days because I hate to come off as a nervous nellie and overall joy killer. You may also know all of this information making my post superfluous for you but it might be useful in the future for others.
However,
I would be cautious using max loads in an old carbon steel heat treated rifle. We don't hear many reports of Krags kabooming but they do not handle gas from a cartridge rupture as well as the Mauser 98 or even the low number Springfield with a Hatcher hole. They also have similar heat treatment to receivers and bolts as do the low number Springfield 1903's for better or worse. People have reporting dropping Krag bolts before on hard surfaces and they have broken due to improper heat treatment/forging. As a single lug design albeit with some passive safeties such as the bolt handle (assuming that the rifle's bolt has not been altered to use the bolt handle as a second lug-not recommended btw) plus the guide rib, Krags did and can shear their main bolt lug in overpressure events. The case rim (although the U.S. military played around with a rimless version) and the fully supported chamber were to reduce the risk of hot gas from a cartridge separation from hurting the shooter or the rifle receiver/bolt by containing the event.
"In October of 1899 a large batch of ammunition for the Krags was loaded to a muzzle velocity of 2200 f/s at 45,000 psi in an attempt to boost the round's ballistics. However, reports started coming in from the field of cracked locking lugs and bullets stripping in the rifling and the ammunition was recalled, broken down, and reloaded to standard specifications.
Those reloading for the Krag (including the 6.5 x 55 mm Norwegian and 8 x 58 mm R Danish) should keep pressures to 40,000 psi and under." (
http://www.frfrogspad.com/kragrifl.htm) This article is footnoted from primary sources such as Brophy etc. on the Krag.
A little more information including anecdotal evidence below.
http://castboolits.gunloads.com/archive/index.php/t-148156.html
Also see plainolddave's comments near the bottom on the Krag comparison with the 1903 low number receivers.
http://forums.thecmp.org/archive/index.php/t-8527.html
The problem with old rifles often comes down to how much risk one is willing to assume--the only sure way to tell a particular rifle's strength is to test it to destruction which kinda ruins the whole experiment unless you are P.O. Ackley.