Stacked-Tube Layout

In a stacked tube marker, two cylindrical sections run parallel along the body of the marker. The upper tube usually houses the bolt and breech, guiding paintballs from the feed stack into alignment with the barrel. The lower tube commonly holds a hammer, striker, or pneumatic ram that interacts with a valve, particularly in poppet based architectures.

This separation allows designers to assign different mechanical and pneumatic tasks to each tube. For example, the lower tube can focus on delivering a controlled impact to a valve stem, while the upper tube manages the path of the paintball and bolt sealing surfaces. Gas passages may connect these sections internally, routing regulated air from lower chambers to upper firing areas.

The stacked tube configuration affects vertical profile and balance, contributing to how the marker feels during handling and recoil. It also influences how maintenance is performed, as access to lower tube components may differ from access to upper tube parts. Although strongly associated with certain historical and contemporary platforms, stacked tube layouts represent a broader architectural category rather than a single design.