.6 inch & .8 inch Wall Piece
Wall pieces were large calibre rifles designed to be used by the defence during siege operations. The British experimented with them in two calibres, .6 inch and .8 inch.
The request for the development of the weapons had originated in about 1879 by the Siege Operations Committee and their requirement was that the weapon should be fired from a rest, have twice the penetration of the .45 inch Martini Henry at any given range and in any medium, be a two man load of around 120 lbs and should not be a shell gun.
The original calibre chosen was .6 inch, but by mid 1879 the Committee were suggesting a larger calibre was necessary and so work was started on a .8 inch version.
Over the next few years considerable experimentation took place with lead bullets, lead cored with steel envelope and solid steel but
surviving examples are all lead bulleted. By about 1888 the project seems to have been cancelled as impractical. The .6 inch gun and mounting weighed 226lbs, far higher than the specification.
.6 inch Wall Piece
"Cartridge S.A. Ball Wall Piece .6 inch RBL" was issued in small numbers in 1879/80, the "RBL" standing for "Rifled breech Loader". It was not approved for issue or shown in Lists of Changes.
The case was a coiled brass Boxer type with a single base cup. the base disc was brass.
The bullet was of lead alloy and weighed 1140 grains with a white paper patch. Case length was 111mm.
The propellant charge was 270 grains of blackpowder.
No other details are known.
.8 inch Wall Piece
Virtually nothing is known of the .8 inch Wall Piece other than a very few surviving specimens.
The case was of typical Boxed construction with a single high base cup. The base disc was brass and case length was 145 mm.
Bullets were of steel and two types are known. The first, shown in the case opposite, was of turned steel with a copper driving band. The second, shown alongside, was similar in construction to the 1 inch Nordenfelt bullet with a solid steel core enclosed in an open copper envelope.
The .8 inch wall Piece appears to have been considered too large and heavy as all references to it cease after 1883/84.