https://www.americanrifle.com/shop/product/mausingfield-bolt-action-2About halfway down the page:
SAFETY AND TESTING
Read this section! You might actually find it interesting and entertaining.
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An action needs to have a margin of safety to resist the dangerously high loads resulting from misuse. The margin of safety stems from both proper design and proper heat-treatment of the steel from which the action is made. Therefore, the Mausingfield action must never be subjected to temperatures above 400°F (204°C) for any reason, because doing so will significantly weaken it and compromise its safety margin. The Mausingfield must not be subjected to high-temperature surface treatments such as ferritic nitrocarburizing or salt-bath nitriding, because such treatments are conducted at temperatures ranging from 900-1200° F (480-650° C). These treatments are marketed under several trade names, including Nitrotec®, Tufftride®, Tenifer®, QPQ®, and Melonite®. While these finishes might be suitable for some firearms, they are not suitable for the Mausingfield and may not be suitable for other bolt actions either.
AND... the last paragraph on THE SAME PAGE that quote came from:
SURFACE TREATMENT
The Mausingfield is supplied with a salt bath nitride surface finish to harden and blacken its surfaces. The resulting finish effectively resists corrosion and reduces friction thus enhancing the smoothness of the action. The bolt head is coated with diamond-like carbon (DLC) surface finish. DLC is an extremely hard and wear-resistant layer on the exterior surfaces. This will reduce the friction between moving parts, thereby enhancing the smoothness of the action. DLC treated surfaces hold oil which enables them to resist corrosion reasonably well.
Check it out:
https://www.americanrifle.com/shop/product/mausingfield-bolt-action-2Whether or not salt bath nitride treatment is a good idea depends entirely on the specific alloy used, the geometry of the part, and the material heat treat condition prior to SBN.
Mausingfield changed their material used in the action and has since then offered salt-bath nitrided finish. The paragraph you quoted from above is old information from the first gen Mausingfield that they forgot to remove from the website. The current Mausingfield Gen 2 is suitable for salt bath nitriding and is offered with it directly from ARC.
