breech·​block | \ ˈbrēch-ˌbläk How to pronounce breechblock (audio) \

Definition of breechblock

: the block in breech-loading firearms that closes the rear of the barrel against the force of the charge and prevents gases from escaping

Examples of breechblock in a Sentence

Recent Examples on the Web The lower receiver in Roh's case does not have a bolt or breechblock and is not threaded to receive the barrel, Nicolaysen noted. Scott Glover, CNN, "He sold illegal AR-15s. Feds agreed to let him go free to avoid hurting gun control efforts," 11 Oct. 2019 The definition is found instead in the Code of Federal Regulations: That part of a firearm which provides housing for the hammer, bolt or breechblock, and firing mechanism, and which is usually threaded at its forward portion to receive the barrel. Robert Verbruggen, National Review, "The ATF Has Been Enforcing a Rule That Does Not Exist," 18 Oct. 2019

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'breechblock.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of breechblock

1855, in the meaning defined above

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The first known use of breechblock was in 1855

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Cite this Entry

“Breechblock.” Dictionary, Merriam-Webster, Accessed 27 Sep. 2020.

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