mike,

When Ruger was redeveloping the SRH for the 454 C cartridge, they knew they needed a cylinder "stronger" than the 44 Mag capable of handling 54% greater pressures. They experimented with several new alloys and decided to use the Carpenter Custom 465 stainless, developed as a candidate for aerospace components, is a premium-melted, martensitic, age-hardenable alloy capable of about 260 ksi ultimate tensile strength when peak aged. In this condition, it also offers higher notch tensile strength and fracture toughness than other precipitation-hardening stainless grades. It provides, in addition, excellent resistance to stress corrosion cracking.
The frame is made from the same alloy as the 44 Mag. you can refer to the article: http://www.cartech.com/techarticles.aspx?id=1608.

What a mouth full!!!!

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