Sorry - I was reading the wrong point of measurement. It would be B that is the measurement across the head of the stock and the 0-frame size is 1 5/8" while the size 1, 1 1/2 and 2 are all 1 3/4".

Apologies... :o





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I just measured a 1 frame and a 2 frame where the head of stock meets the frame not even close the 1 is much smaller . Maybe a error in chart

So much for published data….





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I would think that the B measurement would be the closest to the rear of the frame where the stock fits.