How's about the RatManDu? through or diff?
It is through hardened.
I have stripped one of mine, but I don't have a good enough picture on file right now that would help visually confirm. The temper lines can be hard to get on picture anyway.
But, there is NO temper line.
* I think most know, but along with the RMD, the HRLM, HR, Bandicoot, Rat Hunter, and Dog Skinner are all through hardened as well.
I never had the SAR or Rat Tail, but I am sure they are through hardened as well.
I know for fact the M6 was differentially heat treated with temper line.
Interestingly, I searched through Rat Chat for posts made by Eric and tried every key word I could think of and every combination (RMD, Ratmandu) with (Dif, Differentially, through, temper, hardened) and could not find any posts where Eric mentions how the RMD is hardened. But, I swear I knew it was through hardened before stripping and even before ordering. Maybe I asked on the phone (?????).
But, in any event, it is through hardened. And I don't recall ever seeing any special release that mentioned any different heat treat options.
So, I think it is safe to say they are all through hardened.
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