Vertical sliding breeches and turret space

Would a vertical sliding breech save horizontal space in an 8-inch or larger gun?

Any saving must be assessed alongside ammunition paths, loading machinery and permitted loading angles.

A vertical sliding breech is considered usable for a large gun. Its value depends on the loading arrangement, including ammunition supply and loading elevations. Loading machinery occupies much of the space. A simpler breech can leave the designer with a more complicated loading system.