Kar98k - Reciever, Surface hardened or thru-hardened? (WW2-Style LSR project)

[JBS]

Spot anneal the locations to be drilled by putting the tip of a red hot pointed copper rod on them a couple of times or you can carefully grind away the case hardening with a pointed Dremel stone.

An alternative method of spot annealing if you have a battery charger with a start/boost you can electro heat the spot by using a carbon point electrode. Put a point on the carbon and connect to plus clamp, put the charger ground clamp on the recoil lug, and just put the carbon on your mark and hold until the surface just starts to go past red at that spot. Do this in dim light.

"One can harvest a carbon rod from an old AA or AAA battery."