breechblock

American  

[breech-blok] / ˈbritʃˌblɒk /

Or breech-block

noun

Ordnance.

1. a movable piece of metal for closing the breech in certain firearms.

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breechblock British  

/ ˈbriːtʃˌblɒk /

noun

1. a metal block in breech-loading firearms that is withdrawn to insert the cartridge and replaced to close the breech before firing

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Etymology

Origin of breechblock

First recorded in 1880–85; breech + block

Example Sentences

The list of Russian firsts which pulls Pyatov up from obscurity starts with the adding machine, anesthesia, Antarctica, atomic fission, runs on to the wedge breechblock and the wool-combing machine.

From Time Magazine Archive

L�ger saw his fill of suffering in World War I, but the image he carried away with him was the dazzling light of a breechblock gleaming in the sun.

From Time Magazine Archive

The heavy steel breechblock of the seventy-five was replaced by a wooden block.

From The Story of the Great War, Volume IV (of 8) Champagne, Artois, Grodno; Fall of Nish; Caucasus; Mesopotamia; Development of Air Strategy; United States and the War by Miller, Francis Trevelyan

There was no speck of rust in the unused muzzle, no hitch in the easily sliding mechanism of the breechblock.

From The Call of the Cumberlands by Buck, Charles Neville

In the bore, pent in by the polished breechblock, is a cartridge which has failed in its duty.

From A Gunner Aboard the "Yankee" by Doubleday, Russell