Those wishing to pursue the question should have a look at p. 131 of MacIntosh's Best Guns. Compare the plan view of the M21 "dovetail" in photo top of page w/ fig. 8 above from Burrard. Note that Mac's caption refers to the joint as a "dovetail". It is however, not identical to the true dovetail in the Burrard illustration. The Burrard joint resists lateral separation and sheer and would do so without brazing. The M21 joint would not resist sheer in the absence of brazing. The identifier is the same; the joint is formally and mechanically not the same.

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