im doing a lot of paraphrasing and memory so excuse my errors in what I remember.
think latrobe steel made it, but latrobe is now carpenter. its an aerospace ball bearing steel that isnt demanded much from what I remember, wasnt ever really focused on cutlery more so when big orders came in it was available. seem to remember it was hard to get in knife size setups. so faded away. there is a powdered version....CTS-B75P...spyderco made a mule with it while back. didnt get much attention.
meanwhile while all that above, minus spyderco mule part, was happening.....s30v came in to the scene and well overall...... it was the best made for cutlery steel at its time. so here we are. pretty sure Buck used the last of their bg42 stock up while back.
I like bg42 like to see it come back in buck knives and maybe it will? steels dont really go extinct per say.
you can request a quote for it still from carpenter....see screen shot......
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