I have a Ruger #1 AB in 3006. I just saw a Ruger #1A barrel in 243 listed for sale at a reasonable price. Before I buy the 243 barrel I am trying to find out what would be required to switch over the barrels.on the 3006 action. I know the forend on a 1A is much different than on a 1AB. What other changes would be required. Does anyone know of a reputable gun smith and works on Ruger#1's?

That's a pretty straightforward gunsmithing job. The barrel profiles are the same, so if you can't find a 1A fore-end, yous could always reshape the AB fore-end to your liking.

If the 243 barrel doesn't come with the quarter-rib and sights, and you want them, then you'll need to source those parts too.

I have been thinking about changing out the barrel on a #3. I have seen #1 barrels in various calibers available, Is there any timing issues that a local gunsmith can't handle?

I should think that it would challenge a competent 'smith no more than a bazillion other rebarreling jobs.

While we're on the subject, anybody have or know of a loose Alexander Henry fore arm laying around? I would dearly love to find one.

just buy another Ruger #1 in the caliber you want its cheaper in the long run. maybe sell the #1 you don`t want ?