I've got a buddy who works at in a plant that makes custom hydraulic cylinders.
This was to be one of the components in a "small" cylinder, but it was off-spec and was headed to the recycle bin! In fact, there were three of them!
They were manufactured by a spring company from a specific 5160 melt designed for industrial spring manufacture.
Anyway, they are 1 3'4" stock and were loaded in a pickup with a fork lift!
I can attest to what it takes just to stand one on end.
I can see some LARGE choppers coming from this stock!