Like the Blaser R93, the Blaser R8 is a modular system capable of switching barrels. When changing from one calibre to another within the same caliber family, no bolt head change is necessary. If going outside of the calibre group during a barrel exchange, the bolt head has to be changed as well. However, the bolt head can be exchanged quickly and easily.
Every Blaser R8 receiver will accommodate all barrel contours. However, for an appropriate fit, the proper forearm is also required. Using a forearm for a larger contour is not a problem if the user does not mind the extra gap between the barrel and forearm. A larger barrel contour will not fit in a standard professional stock or wooden forearm though. Extra forearms are available for wooden guns, but not the professional since it is a one piece composite stock.
NOTE: Except for the Blaser Saddle Mount, no R8 components are interchangeable with R93 components.