Yes, steels can be annealed (or normalized) and re-quenched/tempered. Mausers are an excellent example. Been there, done that.
This is a stainless steel action (see dj's original post) and I don't know what stainless alloy Ruger uses in their receivers. If someone knows for certain what the stainless alloy is, then one could think about performing a heat treatment on it.
Without knowing the alloy, heat treatment of stainless can become more complicated than that of carbon or simple(r) alloy carbon steels, hence my suggestion to ask Ruger. They know what alloy they're using and what heat treatment protocol they put it through. If they re-treat the receiver, the liability is back on them, not on dj.
I'm thinking of dj's liability situation.