Well, Sir;
I'm sure you think you have a clever idea. However I would venture a guess that there is a reason why take-down firearms are not manufactured anymore.
1st: Why? The practical market is about zip.
2nd: It serves no useful purpose.
3rd: Expensive hand fitting and precise machining has been passe' since the pre '64 Model 70. Take-down rifles are too expensive to build. (Manufacturers do have to make a profit, you know!)
4th: Normal wear and tear of delicate threads can and will cause excessive headspace. (Safety?)
May I suggest that you find a custom gunsmith that will do the job. Don't ask how much, just order that work done. Take out a 2nd mortgage on you house to pay for it and then report to us how much you like it and that you still think it was a great idea. (I would bet that you will change your tune by then...
)
I would wager that you will spend at least and then some as two new #1s in .25-06 and .35 Whelen.
I do believe that guns with interchangable barrels are an advantage to own in countries where the number of firearms one owns is restricted. Personally I just buy a #1 in any and all calibers I like and call it good. Isn't America Great?
Sorry for playing the devil's advocate, but I fail to see the feasiblity of such a pursuit. Go ahead and flame me, but Puleeze tell us what the final cost is when you get the project done. I don't think there will be a long line waiting....
GH
By the way, I'm sure you are going to state that you won't buy a Hagn or Blaser because they are far too expensive. Well I'd like to buy a new Corvette, for the price of a Dodge Neon, too... But I don't think it's likely to happen in the near future.
Until then, I'll just keep driving my old one.