I spent some time at the range today with Lothar Walther's USA operations manager. Very interesting and nice fellow. He had brought out a custom sniper type rifle in 338 Laupa to test the function and accuracy, using some loads not made up for that specific rifle. The range maintenance crews were cutting grass on the 200 yd range and he did not have time to go through the hoops to use the 400-600 range so he came over to the 100 yard range I use quite a bit. He said he had just got through screwing the barrel on and wanted to test it for function and since he and I were the only ones there I voluntered to call shots for him. The rifle was VERY accurate--he put down several 5 shot groups that measured between .2 & .4"
We talked for a couple of hours and he told me about some of their machinery and equipment they use but said a lot of it was proprietary and ' trade secret' processes and technology was used in their plant. I told him their barrels were highly regarded by several of the forum members I participated in--he was not surprised. FWIW, he said the reason people are not allowed in their plant here is to keep prying eyes away. They do use floating chamber reamers but said the ones they use are about $850 each and they will cut a perfect chamber with the barrel in a 3 jaw. He did not offer to give me any barrels but, other than that, he was a great guy and fun to talk and shoot with.
BTW--the 338 Laupa is one hoss of a cartridge!!