It can be done. I re-read my earlier response and can see how it can be confusing.Well , damn. Thanks for the response guys.
You are absolutely right, Same thread pitch and after turning to diameter there will be a very small remnant of the original 16 tpi so you can pick that up and thread it for the Tikka.It can be done. I re-read my earlier response and can see how it can be confusing.
Let me preface this with this info.... I've never chambered a barrel. However, I am a machinist. The threads won't clean up when you turn it, but it doesn't really matter since it's the same thread pitch. All one would have to do is hit the old threads and start cutting again once turned.
From my understanding, a Tikka tenon is longer than Remington, so the threads would have to be lengthened if that's the case. No biggie. The breach diameter is larger than a Tikka, so it would have to be turned to match up with the receiver. No problem.
As far as the chamber goes, I'll leave that up to a gunsmith to answer your as to whether it'll have to have a reamer run in it again.
As far as making the threads and breach diameter match, it shouldn't be an issue.