It was implied from another thread that John would be using a new "steel" for some of his barrel offerings, in place of the 416R.
It APPEARS that this new steel is 17-4 H1075 Stainless. Here's a quote from his website:
After months of research, development, and testing, we are happy to announce our new Extreme
Duty Barrels. The barrel is made of 17-4 H1075 Stainless with a rockwell hardness of 36-38. This is
30% harder than mil-spec 4150 barrel steel. The barrel is harder, tougher, and more resistant to
erosion than other barrels.
Benefits:
Sub MOA accuracy
Minimal to NO Fouling
Extended Barrel Life
Higher operating tempatures
Looks like the "usual suspects" will be made with this steel.
If this isn't the new steel that is being talked about, then I'm not sure what else is in the works.