As bolt actions go, Krags do NOT have "strong" actions. It makes no difference which component fails - bolt or receiver - the end result is the same. The single locking lug is the weak point - the shock load is asymmetric, and lug contact area is insufficient for more than about 45000PSI. Lapping the main lug so that the safety rib also bears is a poor fix at best, and doesn't make it OK to shoot hot loads, just may give a bit more safety margin.

If you need more pressure, buy a new rifle which will handle 55000-60000PSI. Enjoy the Krag for what it is. It will do almost anything a .308 will do - but if that isn't enough, get a better gun.

Just my $.02.