Search results
Results From The WOW.Com Content Network
The breechblock in a sliding block slides across the face of the breech to close it. The sliding action is perpendicular to the axis of the barrel. When the breechblock slides down to expose the breech, it is referred to as a falling-block, as used in the Sharps rifle. A sliding block is common in artillery. A vertical sliding block rises and ...
A falling-block action (also known as a sliding-block or dropping-block action) is a single-shot firearm action in which a solid metal breechblock slides vertically in grooves cut into the breech of the weapon and is actuated by a lever. [1]
In a falling block or sliding block action, a solid metal breechblock "slides" vertically in grooves cut into the breech of the firearm and actuated by a lever. Examples of firearms using the falling-block action are the Sharps rifle and Ruger No. 1 .
The better breech loaders, however, used percussion caps, including the Sharps rifle, using a falling block (or sliding block) action to reload. And then later on came the Dreyse needle gun that used a moving seal (bolt) to seal and expose the breech.
In British service this became a Crossley pad with an interrupted thread screw block e.g. a Welin screw. The shell was loaded via the breech, followed by the propellant charge in a cloth bag. A single-use "vent sealing tube", a type of primer not dissimilar in appearance to a blank rifle round, was inserted into the breech for firing the gun.
A metal cup on the front of the block, together with the pressure of the screw behind it, provided "obturation" and sealed the breech to prevent escape of gasses rearward on firing. The sliding-block was known as the "vent-piece", as the vent tube was inserted through it to fire the gun. In modern terms it was a vertical sliding-block.
The breech end of the barrel was screwed into a breech ring. The breech mechanism was of standard vertical sliding-block type, but unlike the overwhelming majority of the anti-tank guns of the era, it was not semi-automatic, meaning that a crew member had to manually open and close the breech at each shot.
The gun has a split sliding-block breech mechanism. One vertically sliding block holds a Crossley-type elastomeric obturation ring (which is necessary because the propellant charges are combustible cases or bags) and is locked for firing by a second block. When the second block falls, the first is released to open the breech. [6]