Feeding is not the only issue;ejectors should be properly timed as well. I personally like the Mauser better.In a M70 it's important to keep the ejector slot clean so that the ejector will rise up properly to kick out the case.
I have seen some "untuned" Mausers that left the case sitting in the extractor after the bolt had been slammed back. Replacing the ejector with a military Mauser ejector has solved the problem.
All this sounds really complex, but when one works like it should,it is a sslick as it gets.One of the reasons I'm not much of a WSM fan is that it's hard to get the things to feed well; something like a 30/06 or a 270 on a tuned Mauser or M70 is a delight to use.
One tiny gremlin in converting a pre 64 originally chambered to a standard case like 30/06 to magnum case,is that the underside of the rear bridge should be opened out a bit to allow clearance of belted case on ejection. If you compare an original pre 64 264,300 WM, or 458, action,you will notice that the opening under the rear bridge is wider so that the larger case head can clear the port during ejection. This opening is narrower on an action for 30/06-sized cases.Conversions to magnum I have seen usually do not have this done,but seem to work well enough,although if you are really anal, it is worth considering this.
