A lot will have to do with the current chamber. The K version will probably not change the throating much, so if the current throating is affecting accuracy then I wouldn't expect improvement. If the current chamber is oversized near the base, the K verson won't help there either. But if the curent chamber has excess headspace at the rim which is affecting accuracy, then the K version could be sized to give tighter headspacing and might improve accuracy. I would not expect the accuracy to be worse if the job is done correctly. A better solution might be to rechamber in .222 Rem, that would completely clean up the old chamber and if done right would have a better chance of improving accuracy.
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