Bro. Raimey: I keep trying to 'splain I got no interest in that new-fangled fluid steel stuff wink but thought you'd find this interesting. Even in 1880 canon barrel steel was pretty good stuff. Krupp Fluss Stahl was not introduced until about 1890, and was AISI 1045.

The Journal of the Iron and Steel Institute, Volume 31, Issue 2, 1881
“Application of Solid Steel to the Manufacture of Small Arms, Projectiles, and Ordnance”
https://books.google.com/books?id=BCJDAQAAMAAJ&pg=PA456&lpg
Canon barrel composition
Witten is listed as “Cast Steel in Crucibles” – 3 samples
Siemens-Martin is Open Hearth process – 3 samples
Bessemer – 5 samples
Nobel is M. Nobel (Alfred's brother) of the Tjef Works in Perm, Russia using the Terrenoire process with silicide of manganese. Terre Noire process was developed by Compagnie des Fonderies et Forges de Terre Noire, La Voulte et Bessages near St. Etienne
Bofors Co. of Karlskoga, Sweden (later owned by Alfred Nobel) also with silicide of manganese

……….Witten……...…Bessemer…...Siemens…..….Bofors……..Nobel
C_____.43 - .47_____.15 - .55____.5-.55______.4 - .5_____.12
Mn____.4__________.17 - .48____.12 - .22____.36 - .61___.53
S______.035 - .045__<.01 - .015__<.01_______<.01 - .02___.02
P______.057 - .08___.016 - .042__.014 - .024__.04 - .045__.11
AISI… High P 1044…………………...............…………..1044………1108
Siemens is similar to AISI 1050, but with about 1/2 of the AISI standard Manganese content.


By 1890 the steel producers were obviously attempting to manipulate carbon content, along with manganese
The Mechanical and Other Properties of Iron and Steel in Connection with Their Chemical Composition, 1891
https://books.google.com/books?id=-c8xAAAAMAAJ&pg=PA30&dq
For ordnance material generally a harder and stronger kind of steel is used, although some prefer a mild steel for guns:
Terre Noire: .12% carbon;
Cammell: .14 - .19%;
Vickers: .24 - .27%;
Trubia (Spain): .23 - .33%.
Harder steels:
Firth: .34 - .4% carbon;
Whitworth: .3 - .42%;
Bofors: .35 - .45% (cast without blowholes);
Witten: .47%;
Krupp: .45 - .71%;
Terre Noire: .5 - .88% (cast without blowholes).
“A modern gun being built up of different parts which have to fulfil different duties must not be made of one and the same steel unless different mechanical properties are obtained by different processes of hardening, tempering, &c.”
Barrels for small arms:
Solingen .13%
Terre Noire .3%
Spanish .43%
Witten .47%
St. Chamond .49%
Firminy .57%
Unieux .60%

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