I found this old add dated 1922, I believe I had seen on the wonderful web site shotguncollector.com also probably lifted from there so must give credit to our European Friend( absolutely wonderful work Sir).

Translates We machined to ensure that the stamps on the finished Lauren must have this exact wording; every deviation versatile the counterfeit
Seems to say that the German made Krupp steels were only called this if authentic German Krupp as of 1922.
I assume that means all other names except these were not licensed or from other licensed companies in Belgium?
Do we actually have the tensile strength of these specific 3 steels? Seems like the 3 ring special gewehr lauf steel numbers are all over the place?
I know this has been written about many many times but I thought someone could nail down these three with this wonderful 1922 add?
Thanks

This had to be a re-run advert in 1922 as by then makers would have been touting Inerso-Laufstahl & NiroSta:
patent for the Krupp Stahl NIROSTA(Nitro Stahl - Nichtrostendender) was filed by Krupp on Oktober 17th, 1912.
NIROSTA(NIchtROstendenSTAhl) - Trademark - 1922

Nirosta 18-8
Nirosta 19-9-4
Nirosta V-2A
Nirosta V-2A Extra

https://doublegunshop.com/forums/ub...Words=nirosta&Search=true#Post405086

But all of the run of the mill Krupp tubes find their origin in Liège, where Krupp, Sauer & other's filed patent protections. I am really not sure @ all how Sauer turned out the Spezial Gewehr Lauf Stahl 3 Ringe tubes????? I will have to dig a bit to see if Krupp filed a Patent Protection for the 3 Ringe.

Ah, we'll have to get Hause down here in the Basement to provide some percentages / statistics......


Serbus,

Raimey
rse

Well Doc provided some numbers for Krupp special steel but it’s pretty clear there was lots of stuff floating around with Krupp on it hence this advertisement and the 1922 trademarks/protection.

Sort of paraphrasing Axel E., generally speaking & from a simplistic viewpoint, Krupp delivered bar stock with Cast Steel for Rifle tubes and Fluid Steel for scattergun barrels. Anything else is just advertising that the maker put on the tube to make the end user think he was getting a better grade than run of the mill Krupp Steel. Prima Krupp Stahl is just one such example.

But the makers were supposed to have strict rules from each steel maker and apply those characters when utilizing their steel bar stock. I will search for the tube maker steel stamp rules.


Serbus,

Raimey
rse

The only way to correlate these steel variants is to do just as Hause is doing & having a segment of each steel tube analyzed and making a chart.

Serbus,

Raimey
rse

The sauer tubes I have are written just like the advertised above, but the other German trade guns both Suhl, Zella,Lindner, Leberecht, Schurk, Kessler all have the other Prima- Kruppsher- Fluss Generic Krupp lingo. I’m guessing all but the Sauers were Belgium licensed tubes.

The general consensus is that ALL rough bored tubes came from Liège, so even Sauer sourced tubes from Liège and that's why they filed for patent protection for the Wildmann with a Staff and others. But I just cannot remember a Sauer 3 Ringe protection. I will have to search.....


Now I am not sure how much the Austrian's sourced Liège, but everyone else including the Americans were....



Serbus,

Raimey
rse

The water discharge pipes in my childhood home, built in 1948, were marked KRUPP. Apparently, the USA shipped Krupp products out of Europe after WW2, to be resold to American contractors.

Probably few will read this, but even if true, it does provoke some thought:

https://www.newsbreak.com/news/3132...ng-it?noAds=1&_f=app_share&s=a99
(Copy & Paste)

So those pre-WWII steel tubes may just have a bit more intrinsic value???


Serbus,

Raimey
rse

Interesting. Thanks for the link.

the range of information that shows up herein can be fascinating....just one more of the untold number of things that i did know...and, i'll admit that i often find myself in general agreement with the second guy who commented at the end of this article.

best regards,
tom

very very interesting !

I read this Krupp steel thread with interest, and it made me recall a section in Donald Dallas' book 'Purdey Gun & Riflemakers', where he states " for a time in the late 1890's, Purdey used Krupp steel from Germany( Whitworth was temporarily unavailable). On 27 August, 1897, James Purdey wrote to his son Athol: ' The tubes of Krupp have been tested and are found much stronger and tougher so that we can use them satisfactorily and perhaps more than the Whitworth. However, by the early 1900's, Purdey had reverted to Whitworth." It doesn't state what grade of Krupp they used; three ring, etc., but this is an interesting comparison between a steel (Whitworth) that makers charged quite a premium to barrel a gun with, and Krupp, which was used on many mass- produced American and European guns, costing from $25 on up. Regards, Sandlapper