Gloria a Dios the 20g M12 Nickel Steel barrel arrived. It has what is almost certainly an obstructional burst centered about 6" from the muzzle. I'll work on some good images.
Should get a segment over to METL Friday morning for both composition and tensile strength testing.
BTW: The 1913 edition of “Halcomb Steel Co. Catalogue and Hints on Steel” is digitized
https://archive.org/details/HalcombSteelCompanyManufacturesOfHighestGradeCrucibleAndElectricThe first electric arc furnace was developed by Paul Héroult, of France, in 1900. Héroult came to the U.S. in 1905 and Halcomb installed the first electric arc furnace in the U.S. in 1906. Sanderson Brothers installed an arc furnace in 1907.
p.48 “In the operation of the Héroult Process we start with molten open hearth steel as our “raw” material. (the electric furnace) removes sulphur, gases, oxides and slag, and at the same time (we) adjust the composition with accuracy and precision.”
“The Héroult Process permits less variation in alloying constituents by other process and even the percentages of easily oxidizable metals like chromium and vanadium are controlled with great accuracy. Having produced
steel thoroughly deoxidized, chemically of greatest purity, free from slag and segregation…”
p.53 “3 1/2% Nickel Steels” (Ni 3.25% - 3.75%)
.20% C with Elastic Limit (Yield Strength) of 57,500 psi and Maximum (Ultimate Tensile) Strength of 82,000 psi
.30% C with E.L. 63,000 psi and M.S. 93,500 psi
.40% C with E.L. 65,000 psi and M.S. 94,000 psi
p. 57 has a “Specifications for Automobile Steel” chart as recommended by the SAE. This was long before the AISI standardization numbering system, but the chart documents the recommended concentrations of manganese (.5-.8), phosphorus (<.04), sulfur (<.04) and the alloys.
Mike Hunter has looked into the Forum, and hopefully he will comment after the results are in.
