Ffixer, it's the spent case bin mounts that have been cut off, and rather crudely, compared to where the part 6 shown in the drawing has been cut out of the centre.
Found the missing rear pin and made a new catch plate/bolt /chain for it, you can see the rough cuts in this pic.I have tidied it up now and will wait till/if I find a bin to fit before making new mountings for it.
Found this pic of a mk 1, it has the centre cut out like mine which makes me think both are modified mk 1s. as they both differ from the drawing.
Could the rest of the bin mountings on mine have been cut off in service for some reason?
Just one more thing, can't find any info on the functioning of the sights 2 & 14 in the drawing, could you enlighten me please?
Link to one for sale
http://www.dandbmilitaria.com/British-GPMG-Vehicle-Mount.html
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