A round action (Rem 700 clone) especially with a smaller port is going to be more rigid, more symetrical and EASIER to make shoot great. It will take much more care and skill to get a Mauser to shoot as good and I don't think the end potential is as good. If it was, you would see them in some of the accuracy disciplines. With one exception, I have never seen a Mauser action at a rifle match. I also don't think there is any need for a hunting rifle to shoot much better than 1 MOA. How many of us really shoot far enough that this matters? Sure, it is fun and nice to brag about and to some degree a confidence builder. When I put together a long range hunting rifle I use quality 700 style actions with the accompanying excellent triggers, scope rails and stocks that abound in this configuration. I also quit load testing once I hit .5 MOA as I feel practice is more important that chasing the holy grail of accuracy. I only get about 600-800 rounds out of my 6.5-284 barrels. I hate burning them up looking for 1/4 inch groups when 1/2 inch groups are more than good enough.
IMHO the majority of accuracy gains in the past 3-4 decades have been from barrel quality and the care gunsmiths use to chamber those barrels. I haven't found it any more difficult to work up loads in a mauser 98 than a Remington 700 and I've done so in multiple configurations of both actions.
If my goal was 10 shot groups of 1/2" at 100 yds, I certainly wouldn't choose a 98 mauser as a basis in fact I'd skip the 700 and go with a custom action builder. If I was content with three shots in a 1/2" and maybe some change, I'd not hesitate to choose a mauser, and have a good gunsmith fit a top match grade barrel.
The reason I stopped using Mauser 98 actions is they are heavy and clunky and starting with a military action and converting it to scope use with a good trigger costs as much as buying a complete new factory rifle that is lighter and likely good to go out of the box.
