I checked sorby's website and they don't mention their tools being made of
M2 HSS. My guess is packard has it wrong

All the turning tool sellers and manufacturers said there tools were made of
A2 HSS a couple of years ago but most have removed HSS from their tools
cause it was a mistake... BRBR

Why can't you admit it? Go into any store or look in any catalog that sells
Sorby turning tools and you will see "HSS" stamped on every gouge, skew,
scraper that Sorby makes. If Sorby turning tools were not HSS they wouldn't be
able to compete with all the other Manufacturers that are. As someone else
said, it's easy to tell HSS from carbon steel by the way they look on the
grinding wheel. HSS makes a light yellow spark, and carbon steel makes a
darker, orange spark that breaks up and bounces all over the place. Trust me,
Sorby turning tools are HSS.
-Jim Gott-
San Jose, CA