Yes the Stolle Panda barrels are coned and as such, if one wants to re-thread for Rem 700 you have to cut the existing threads off. Barrel shank is 1.233 inches in diameter for 2 inches past existing threads.
Spoke with my gunsmith from E.R. Shaw and he said that 0.875 inches is needed to re-establish threads for Rem 700. So looks like you would only loose this amount of barrel length and could re-chamber for cartridges like the 6mm BR, .243 Win or 6mm Rem. Hope this helps answer previous questions.