No. 32 Mk.III construction/design question

[Peter Laidler]

Good question and I'll have to look at the technical spec during next week BUT offhand, I don't think that the distance you mention is relevant as I have seen them differ greatly. Another problem is that while the grat is .006" (I have noticed that some are slightly thicker, at .0068") and the X wire is .001" (....although the L1A1 spec says that it is .0008"....) this is the simple bit. The HARD bit would be getting a constant distance between the tip of the pointer and the crosswire because due to the magnification of the two plossl cells (the erector and the ocular don't forget....) the actual size of the grat is magnified x25 or x27 or so I seem to remember but feel free to correct me if I'm wrong.....

Knowing this magnification, it'd be virtually impossible to get a constant distance you speak of.

However, you can use the grat to approximately judge width and height by knowing the obscuration factor (that is the width the grat covers at X yards). The sniper courses used to use this to guestimate things on the old courses, with L42's/L1A1's and the early L96 S&B scopes but the new ones (the big x4 to 12 scopes) don't cater for these little wheezes

It's getting into the optically complicated now and my optical engineering tutor from uni days, the kindly Mrs Macintyre said to me during a tutorial once '...try not to be an optician in later life Peter.....'