Tucked away in the archives of this collector's forum is the wealth of information, not me. Learn to use the search function, and how to visit the archives. A major portion of what I know about Schrade knives and the people behind them came from THIS SITE. And from reference resources these folks opened my eyes to.
As a generalization, the Old Timer knives were 1095 (and their scrimshaw counterparts), and the Uncle Henry line was stainless until the late eighties, early nineties. Then it gets muddled as they began using stainless on Old Timers not marked as such. Of course, the stainless mark was "SCHRADE+".
A blade carrying that mark is nearly always stainless. But all stainless blades are not marked as such. According to a factory source, the stainless stock became cheaper to use and store than 1095, and theybegan a gradual changeover for most of their patterns. The only reference (so far), besides this site which has information of the various Old Timer and Uncle Henry patterns (production models) is Robert Clemente's book. A few others discuss special and limited editions. So far there is not an exhaustive reference on Schrade knives. No Stockman, there is not such a website unless you count this one.
I do not pretend to be an expert in metalurgy, so the question of the heat treat is to me a difficult one. I own and use their knives in 1095 from many years timespan. Occasionally I find one a bit harder than the norm, and a bit softer too. For the most part, they were quite consistant as far as I can tell.
Codger