The Mauser shroud as stated is the last in a line of gas deflecting devices. The pre-98's lacked the flange that the 98 added. However, that shroud is a last resort. Unlike the Rem 700 which is designed to contain gases, the Mauser seeks to redirect escaping gas. The problem with the Model 70 is that there is nothing that prevents gas from running down the left siderail and past the shroud straight into the shooter's left eye. The Mauser had the shroud as mentioned, but before that the gas had to get past the huge bolt stop, and prior to that gas was bled off by the thumbcut.
Now, it is probably safe to say that brass today taken on the whole is better than that made when the Model 70 was designeded. But, it is not perfect and neither are shooters and reloaders. The June 2010 issue of handloader has a nice article showing all sorts of factory defects in brass. So, counting on your brass to never fail will be a big disappointment to some.
That said, one of my favorties is a Model 54 I own. Just be sensible and wear shooting glasses.
