Tentman,
Restoring a fine rifle like an original Mauser K actioned sporter in .250-3000 is a very worthwhile endeavor; and worth doing correctly. Find an original commercial bolt to shorten; either standard or intermediate length. The work is fairly straight forward and most of the cutting and fitting can be done in a lathe. The rib of the bolt is used to insure correct alignment of lugs etc. and the cut should be made in the middle of the rib. The trickiest part is getting the length exactly right so the rear lug and bolt root fit correctly. Shortening the firing pin is realitively easy; and the extractor is the same for K, intermediate, and standard actions.
I have done the two action cut and swap, and it works out well; although it is much more work than one might think. I started with an older commercial large ring small shank action that had been buggered quite a bit, and a "Standard Modell" action with Mauser crest on Reciever ring. I ended up with a magnum length action with crest, and a K small ring[the larger ring was turned down] solid side wall, action correctly marked with "Waffenfabrik Mauser Oberndorf a/n" on the side wall. Both actions recieved square bridges. The bottom metal for the K was made from an Argentine guard assembly, shortened at the rear, and with floorplate made into a "straddle" type. I had an original magnum length bottom metal for the other action. Magnum length actions have the recoil lug at the rear under portion of the reciever ring, and this had to be fabricated and welded to the action in order to use the original magnum metal. After all this work, the action was re-heat treated.
Good luck in your project.
Mal
