Editing Breechblock (section)

=== Sliding block ===
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 falls while a horizontal sliding block slides to one side. It is a strong design. The breechblock is well supported by the receiver within which it slides and the mechanisms for opening and closing the breech do not have to act to any extent against the forces generated on firing.

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File:Sliding-block-action.png|Operation of a sliding block
File:Sharps falling block action.jpg|Looking at the breech of a [[Sharps rifle]]
File:Ruger no1 243 right open.jpg|[[Ruger No. 1]] single-shot falling-block rifle in [[.243 Winchester]] with custom barrel with action open
File:25 pounder breech CMHM Brantford.jpg|The open breech of an [[Ordnance QF 25-pounder]]
File:M101A1 Howitzer Breech and Carriage 20121013a.jpg|Breech of an [[M101 howitzer|M101A1 Howitzer]]
File:Keilverschluss 1862.tif|upright|Section of the double wedge sliding breechblock of a [[C64 (field gun)|C64 field gun]], an early breech-loading field gun.<ref>{{cite book|title=Atlas zum Grundriss der Waffenlehre|publisher=Literarisch-artistische Anstalt|author=Sauer, K.Th.von|year=1869|location=Munich}}</ref>  The sliding breechblock consists of two opposed wedges.  The screw mechanism moves the wedges relative to each other, to change the effective thickness of the breechblock.  Expanding the block locks it in the closed position and seals the breech.
File:Spencer rifle diagram.png|The [[Spencer repeating rifle]] uses a falling breechblock (F) mounted in a carrier (E).  Figure{{nbsp}}1, shows the breechblock raised.  Firing forces are contained by the receiver at the rear of the breechblock.
File:Spencer Carbine Mod 1865.JPG|The Spencer repeating rifle with the breech open.  Before the breechblock carrier can "roll" downward, the breechblock must fall vertically to clear the receiver.
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