1. What does the S, BT, SBT, HS, HSSR and the like stand for?
As for the "HS" and the "HSSR", they designate M2 high-speed steel blades with the first being plain edge and the latter being ComboEdge. In both cases the M2 blades are BT2 coated since this steel type has a higher carbon content.
Just to complete the coding system discussion, we offer a "CG" (chisel-ground) blade in the Model 910.
pardon me if i'm wrong, but HS indicates M-2.
the extra S would indicate serrations on any BM. SR indicates serrations on M-2.
BM does make a 710 HSSR. i had a 710SBT and the serrations were on about 40% of the edge and having them on the recurve part seemed to actually help because the blade would bite into whatever you were cutting even more. that's my personal observation though.
i have a 710BT now and kinda miss serrations =(
the crazied knife weilding Sarah McLachlan fan =)
I think Knife Fumbler straightened that out.
I recently ordered the 710 in M2, and with a plain edge. The designation is 710HS.
I'm getting away from partially serrated blades, but like them on my work knives. The serrations make starting a cut much easier on some materials (heavy rope, multi-layer rubber hosing, plastic straps-all stuff a plain edge has a lot of trouble with). Fine for work, but away from there, I no longer care for serrations.