Sure, I am very interestet

thought about it the last days and my conclusion was that this cartridge must fit in a military mauser action. this is essential for a Schüler cartridge but thank you for your clarification about the cartridge oal. I would use a common M 98 action and build a single row magazine for it. knowing that many gentleman dont like it when the magazin is not flush with the stock but I can live with this.
the feeding problems with rebated rim catridge's occur only in double row magazine's. you never hear this about the .50 Beowulf in the M 16 for example only to talk about the latest succesful rebated rim cartridge. I have study this problem in my 11,2x60 Schüler Mauser rifle and the problem with the rebated rim design is in a single moment in the feeding prozess. the cartridge in a single row magazine move in two directions: up and forward
in a double row magazin the cartridge moving up , left or right and forward.

there is a moment when the case head can slip under the bolt head when the feeding is not made 100% perfect by the gunmaker but only in double row magazine's.