I have been stalking this rare bird for about a month now and finally captured it.

http://www.gunsamerica.com/911819554/Gun..._Mauser_270.htm

"1922 Newton Mauser, converted in 1930's by Niedner Rifle Corp to .270 Win, in our family since new, Mauser action, spoonhandle bolt, 2.5 power Lyman Alaskan scope, Redfield mounts, set trigger, folding express sights, beautiful grained medium dark walnut, hand checkered, very good condition, stamped Niedner Rifle Corp Dowagiac Mich on left side of barrel, stamped number 1242 on bottom of barrel, overall very good condition, seldom used."

Speed's book "The Mauser Archive" goes into detail concerning the Newton rifle, and contains the statement:

"Again his (Newton's) strategy was to import new Mauser rifles from Germany chambered in Newton calibres....the new rifle sold was a Mauser action fitted with a Mannlicher pattern bolt handle, a new style reversed double set trigger, 3 leaf sights, front sight base milled from the barrel material, and a Newton designed stock of European walnut....These well made rifles were manufactured on contract in Germany, and went on sale in the US in 1922 as the Model 1922.

Unfortunately, Mr. Newton only received one order, for approximately 100 Model 1922 rifles. The cost of doing business in post-WWI Germany was cited as the reason for terminating the project."

Speed concludes that the actions were made by Mauser Oberndorf, incorporating the same turned down and flattened bolt handle as used with the Mauser Type M (Mannlicher) sporting carbine and that the work on the remainder of the rifle, including the special reverse curve double set trigger performed by a firm such as Sauer.

In any case, what we have here is a rare Newton 1922 made even rarer by the Niedner connection. Presumably the original .256 Newton barrel was shot out or ammunition became unavailable, and the rifle was sent to Niedner for conversion to the relatively new (1925) .270 Winchester cartridge.

According to the table in Michael Petrov's book, "Custom Gunmakers of the 20th Century", the barrel number would indicate that it was installed in 1935, which would have been three years before the discontinuance of the .256 Newton as a commercial cartridge