Model 10 Ross Sights With Volley Sight Alteration, Need Help To Identify Its Purpose?

[buffdog]

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If there are a couple of grooves on the bottom round part where the hole is, try them on a SMLE. It could be an experimental attempt to give more flexibility to the Volley sights. The Canadian Army had .22 Calibre rifles with Cooey made Ross sights mounted on them for training purposes. Is the "HWC" marking on them?

BSA made a .22 Calibre rifle intended to simulate the SMLE but in .22 Calibre. Maybe .22 Martinis?

Also, at the start of WWII, some Ross rifles were modified to a semblance of the Boyes .55 Calibre anti-tank rifle. Since these seem to be offset to the left, it is possible that these sights are for that alteration.
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