Thanks for this Rothhammer,...
This brings me to the somewhat enigmatic "T in a circle" proof mark on the action and barrel. It signifies "Tiegelgussstahl" (crucible steel) and is said to date post WWI. However the only reference to post WWI and this mark that I can find is that it began use on Czech production guns post WWI.
I cannot find any source that mentions actual starting date of usage by Austria.
- Mike

It would be interesting to chase down the source of the 'after WW1' quote regarding Tiegelgusstahl which, as you've noted, means 'crucible steel'.

I suspect it could be a 'fact' that has been oft repeated and has thus 'grown legs', becoming apocryphal over the decades. What was the actual source? Are there any very old German or Austrian metallurgists about?

*** I may be on to something, here:

Found on the 'net-

The melting furnace for crucible cast steel was already in place by 1847

Written by chronicler on Monday, October 5, 2020, 12:07 a.m. | 0 comments

By the year 1850 the problem of cheaper raw materials became acute. The unexpected upturn in means of transport, the livelier trade in trade at home and abroad, the beginning displacement of manual work by machine work and better processing options for the material depressed the value of Remscheid products. It was therefore a vital question for the entire Remscheid economy to lower the price of raw materials. The transport of the material remained time-consuming and costly, as a direct rail connection for Remscheid was not created until the end of the 1960s. The only way to reduce production costs was to produce cheaper locally the steel, which became the main raw material for the tool industry and replaced iron. So created

The Lindenberg steel works, also known as bell steel works, emerged from this factory.According to old invoices, JA Henckels obtained cast steel in Solingen from a Lindenberg company in Remscheid as early as 1847. As far as could be ascertained, the Lindenberg & Co. company probably operated a melting furnace for crucible cast steel at Hammesberg on a trial basis in that year. However, nothing more could be learned about this than that Henckels tried out this steel. -With the significant fact that the factory production of cast steel began, we encounter the name Mannesmann, which often appeared among the promoters of the Remscheid industry in the course of the 19th century. Various attempts by other Remscheid companies to produce a steel suitable for making files themselves had failed. When in 1853 the first attempts by A. Mannesmann to manufacture cast steel in crucibles were successful, from 1856 onwards it included the need for the uniform and fault-free material required for the manufacture of quality tools in its list of its own products.

In a report by the Lennep Chamber of Commerce from 1864, an unfavorable judgment about domestic cast steel is expressed, probably due to the attitude of bias towards foreign products. However, such criticism soon fell silent in view of the fact that, supported by entrepreneurial spirit and engineering skills and supported by a well-trained trunk of skilled workers, the scope of cast steel production in Remscheid quickly increased and the quality of the products improved.

With the advent of the new types of steel and the increase in goods production, however, people were forced to resort to new ways of working. The process of hammering out the steel and iron bars (the raw material of the old small forge shop and their processing into strip and plain iron in the horizontal and wide hammers operated by water power) was quite laborious. The rolling process took its place. This was the fate of that group too Sealed by water hammers. Only here and there can still be found today in the valleys of the Remscheid, Cronenberger and Lüttringhauser areas a horizontal bar or broad hammer in action, in which files and other tools, cake pans, trowels etc. are knocked out. What a cheaper production thanks to the rolling process we see from a report by Friedrich Harkort,

expanded it in 1869 and added various new facilities, including what was then the largest water wheel in the whole area. As we learn from an old "price courant" of the company, she produced sheet steel from 0.5 to eight millimeters thick (for saws, scrapers and springs of all kinds) and also had them processed into goods for their own sales.

The development of rolling technology as a means for the first shaping of iron and steel led in 1860 to the conversion of the previous Bökerschen grinding shop at the "Wendung" into a rolling mill.

How big the Remscheid steel consumption was at that time, we can see from the company's prospectus, which increases it to 41,500 ct. In file manufacturing, 23,770 ct. In sawmaking and 2,500 ct. In the factories that manufacture other tools, thus a total of 67,770 ct. figured. However, after the company was liquidated after just one year, the Böker family - mainly Heinrich Böker - took over the factory in 1861, brought in the rolling mill technician A. von der Nahmer and created the first efficient company under the name of "Gebrüder Böker & von der Nahmer" , in Remscheid itself located rolling mill.

From the early 1870s, the only Remscheid sheet metal rolling mill of the Arns brothers at that time, the steel sheets required in particular for the production of metal saws were rolled out. "The beginning was difficult, as it was necessary to fight against the well-known, even today not completely vanished prejudices of the saw manufacturers that a good saw can only be made from English sheet metal." Now the hacksaws, which had hitherto been spread out of bar iron under waterfall hammers and forged by the sawmith, could be made from sheet metal, just like the saws for woodworking.

The crucible cast steel production in Remscheid was in most cases connected to the rolling mills, so that independent rolling mills were always an exception. In 1865 a cast steel smelter was built in the Böker factory. Together with the rolling mill that had previously been built, it formed the beginning of the "Bergische Stahl-Industrie". This new establishment, like that of the Stachelhauser Stahl- und Walzwerke Hessenbruch & Cie to comply and to resolve the difficulties of obtaining a good steel, the quality and uniformity of which must not fluctuate for fine goods; because Westphalian,

The intention to provide the Remscheid economy with a raw material basis by creating local steelworks and thereby to compensate for the disadvantages of the unfavorable traffic situation was of course overtaken, since at this time (1868) the railway connection line Remscheid-Barmen-Rittershausen connected the Bergisch industrial area with the Ruhr district and allowed the cheaper procurement of the raw material.

However, the steel consumption became so great that the Remscheid steelworks nevertheless retained their important role in supplying the local companies. That is why we have to take a brief look at the development of the two largest of these plants, the Bergische Stahl-Industrie and the Glockenstahlwerk. (based on: "From the history of the Remscheid and Bergische tool and iron industry" by Wilhelm Engels and Paul Legers, published in 1928 for the 25th anniversary of the employers' association of the iron and metal industry of Remscheid and the surrounding area, 1979 by Ute Kierdorf reissued as a facsimile print. Here part II, Paul Legers: The Remscheid tool and iron industry from the introduction of trade freedom to the outbreak of the World War)

Source: https://www.waterboelles.de/archives/15090-Schmelzofen-fuer-Tiegelgussstahl-stand-schon-1847.html