This is the website of Lothar Walther here in the USA:
Lothar Walther
Woody Woodall is the owner of this company. I have had the great pleasure of many excellent conversations with him over the last 20 years. I'm not saying that we are best friends, rather we seem to have terrific conversations when we run into each other at a trade show or I call him on the phone to tap into the huge compendium of information stored in his memory. He is a true Mauser aficionado and is deeply devoted to barrel manufacturing and firearms.
As to the steel (LW50) that Lothar Walther uses:
** I have done no editing; this is exactly as received by a member on another site. **
This is the answer I received directly from Gerd Walther:
For you in AISI, it is the 420 alloy.
"I presume their supplier is Boehler Udderlohn in Austria." ed comment
R.G.C
The material we use is specialy made for us and we order not through a dealer, we order directly from the steel company here in Germany and Austria. We have the name in our house LW 50, the offical material name is X20Cr13 or if you like to look into the Stahlschlüssel, it have the number 1.4021. The steel is in a special way straightened, controled and headtreadet for our product. We know about that it isn`t easy if you like to work by your self with the steel,specialy with the standart chamber reamers which available on the marked) here all have to be corect, the tool have to be sharp speed and feed have to be corectly and it have to be used a special metal cutting oil.
Here is a metallurgical reply from another member:
AISI 420 is a Martensitic stainless commonly used in kitchen and surgical knives. It is not related to PH steels, requiring quenching from transformation to increase material condition. It is regarded as tough and stringy when machining. Steels with this characteristic often require special cutter geometry to achieve optimal results.
During one of the first conversations I had with Woody, he suggested that I increase the RPM of the barrel when chambering and use an oil with high sulfur content for chambering. He also spent a few minutes describing the reamer geometry to optimize the cutting of the chamber. At the time I was intent on using LW barrels for several projects so I got my reamer maker on board with the geometry in order that I could get several reamers made. I can describe the geometry as slightly more 'aggressive' than the standard reamers and they were made in carbide.
Following the procedures outlined by Woody, I never ran into any of the problems suggested here. The threads were excellent and the chamber took next to nothing for a final polish. More RPM, more sulfur oil with a slightly more aggressive reamer is all it takes.
I realize that there are few if any gunsmiths who will order special reamers just to use LW barrels so I think we can skip the potential criticism from that aspect. I understand the reasoning completely.
As to accuracy, this sums it up without me having to rewrite something:
"The guys that compete will spend whatever necessary, no matter where it was made. If they thought LW would put them in the "rankings", they'd use them. LW might be fine for a hunting barrel, but the question was about accuracy, not what degree of accuracy, but accuracy." -shortgrass-
All I can say is that for the dozen or so barrels I used, the accuracy was superb. I have no regrets and the clients were thrilled.
I have had the pleasure of using all of the top barrel maker's barrels. John Krieger's are right up there kicking and screaming. I don't have any problem using them when specified by a client although I use more Bartlein's than any other by a huge amount. I think that any gunsmith can order from all of the top makers and get a product which will serve their needs perfectly.
Regards.