they sure make life easy when you are developing ideas you want to be easily interchangeable...
The primary reason for the carbon fibre sleeve is to stiffen the barrel and improve accuracy by reducing the amplitude of barrel vibration during the shot cycle.... I will further tune out any remaining vibration with the harmonic tuner on the muzzle, which is a movable weight that will allow me to have the bullet exit from the muzzle coincide with the momentary pause of the barrel at the end of a vibration, by tuning the frequency at which the barrel vibrates.
I don't think finding a "node" should be a problem with our relatively low velocities....