Craig: this is the analysis of a 1898 00 Hunter Arms Armor Steel barrel.
Carbon .47%
Manganese .68%
Phosphorus .112%
Sulphur .075%
Nickel .02%
Chromium .02%
Molybdenum <.01%

Tensile Strength 101,000 psi

METL’s analysis: “The chemical composition the Armor Steel sample was determined by optical emission spectroscopy (OES) per Fed Test Standard 151B, Method 112.2. The measured results are comparable to 1211 rephosphorized and resulfurized low alloy steel (UNS G12110) as well as 1045 plain carbon steel (UNS G10450). The carbon content was higher than the common modern domestic alloys within this group however.”

Non-deep thinkin' version is non-standard 1045

https://sites.google.com/a/damascusknowledge.com/www/home