[Floreos]

Originally Posted by ThunderCactus

65 hardness of what could only be the rockwell B scale indicates they're using a stock material. Most likely a cast steel part, due to its complexity and apparent finish, especially the pictures of the back of it.
If it were 65 rockwell C, due to the design of the part (I'm not exaggerating) if you dropped it on a concrete floor from a height of 3ft, it would break.

If they really WERE smart, they're be using higher end alloys. 4140 is a very common steel grade, comes in at 25 rockwell C, and is VERY low wearing in this sort of application. Heck, even something like 1022 would be better than what they have now. But with billet material, they'd have to machine from billet, and that's way more expensive than castings.

Basically, his bolt catch is about as hard as good aluminum. Which is crap for a ferrous material.
I doubt his bolt carrier is made of much better stuff.
It's possible there might be an engineer somewhere that knows what they're doing, but ultimately they're subject to the manufacturing process.

So much like FCC, the bolt catch may have been the greatest thing ever in prototype, but in production, it is apparently garbage lol
It's too bad the gun doesn't use RS bolt catches.

Well I'm not saying it's a good part that's for sure. I'm saying it's not a heat treat problem.

As the OP suggested it's probably crap metal on purpose.