How to Change Mauser Barrels

Inspect your Mauser to be sure that its barrel does indeed need replacing. Using a magnifying glass and an area with good lighting, check between the grooves, the lands, and along the length of the bore for rust. Especially if you can see sharp differences between corroded and non-corroded areas, the barrel must be replaced.

Apply a thin dusting of rosin to the barrel blocks, which will help the wood grip the metal of the barrel.

Tighten both sides of the vise equally around the barrel. Don't worry if you break the barrel blocks; it should not affect the barrel.

Use the barrel nut wrench to begin loosening the barrel nut in even, long strokes. If the barrel or action begins to turn, stop immediately, loosen the vise, and once again attempt to tighten the vise around the barrel -- tightly and evenly.

Remove the stock and other components from the barrel carefully, setting each aside on a cleared workspace.

Release the vise to remove the old barrel, and set it aside.

Set the new barrel into place in the vise and cinch it down. Thread the barrel nut onto the barrel shank with the nut wrench. Continue threading the nut until you run out of threads.

Find the recoil lug and place it carefully onto the action of the barrel shank, and thread it onto the action. The dimple on the recoil lug should face the action, lining up to the small cut on its surface.

Insert the headspace gauge to set it correctly for the Mauser's caliber and then close the bolt over it. In some cases, short-chambered barrels can be obtained for Mausers, which will accommodate for smith inconsistency in this step.

Thread the receiver onto the barrel shank and tighten it with your fingers until you meet resistance. Continue tightening with the barrel wrench.