If you own a Savage bolt-action rifle, you can change calibers by swapping barrels yourself. Lane Pearce shows you how in these easy steps. Follow along as he swaps his Savage .204 Ruger-chambered barrel for an aftermarket barrel kit for the Savage chambered to .243 Winchester.
Use the "GO" and "NO-GO" gauges to set the headspace. That is a critical procedure. Install the new bolt assembly into the action, carefully insert the "GO" headspace gauge under the extractor into the chamber. Close the bolt completely and thread the action onto the barrel shank.
As the gap between the barrel nut and action is closed, be sure to position the recoil lug on the face of the action so its key engages the corresponding notch in the action. Continue to thread the action assembly (counterclockwise) until the "GO" headspace gauge is firmly seated in the chamber. Turn the action/boltface until it is just hand-tightened to the barrel. Make sure the recoil lug is still positioned correctly and turn the barrel nut clockwise, by hand, until it jams the recoil lug flat against the action face. Hold the action and barrel together firmly and remove the bolt from the action. (This step is much easier to do if a friend helps.)
Be sure to catch the "GO" gauge when you retract the bolt. You must make sure that the barrel and action do not move (rotate) relative to each other. Finally, snugly torque the barrel nut (clockwise) with the wrench to securely "jam" the barreled action assembly together.
Here's where both headspace gauges are used to verify if the barrel and action are mated correctly. After you install the bolt assembly, insert the "GO" gauge into the chamber, and gently attempt to close the bolt. It should close completely with minimal effort. If it doesn't, then the chamber headspace is too short (tight) and you won't be able to chamber a round of ammo. Back the barrel nut off and repeat the barrel/action/bolt/"GO" gauge fit-up steps.
When you pass the "GO" gauge check, the next step is to try the "NO-GO" gauge. It is machined to be a few thousandths of an inch longer than the "GO" gauge. When you insert the "NO-GO" gauge into the chamber and gently attempt to close the bolt, the bolt should only close about halfway if the barrel and action are assembled correctly. If it closes completely, there's too much headspace, and it may be unsafe to fire the gun. You must loosen the barrel nut and repeat the reassembly and checkout steps.
Assuming the headspace gauges indicate you got it right, all that remains is reinstalling the barreled action into the stock. Align the trigger and magazine with the stock inletting and insert the barreled action into the stock. Be sure to hold everything together by hand and bump the buttstock sharply on a rigid surface to assure the recoil lug is fully seated in the stock. Drop the two action screws into the appropriate holes and turn them in with the Allen wrench until they're firmly hand-tight. There's no need to overtorque!