Heat treat of US Krag's bolt body?

[Naphtali]

What is the alloy used in US Krag rifle bolt bodies? I believe the AISI 1325 used in its receiver is not what is used for its bolt body.

Is the bolt body heat treated uniformly? If it is, briefly describe it. If it is not, what occurred to obtain the Krag's remarkably smooth operation?

Is its [front] locking lug uniformly hardened through the entire lug? If it is not, what is the surface depth of lug's hardening and what is its HRC hardness range?

[gnoahhh]

I would pose the question over on the Krag Collectors Association website. There are guys there who live and breath that stuff.