The Original Diana monobloc was patented in 1881, in which the tubes were inserted from the breech with a step from the steel breech to the pattern welded tubes

"Forest & Stream" 1882

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Beretta referred to the process as the Brevetto.

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I don't know what Manufrance called it.

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Then in 1903, like the Modified Diana, Beretta inserted the tubes from the front; without the step

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A process now used by almost all of the Italian makers, with an occasional failure

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