Thanks for everyone's reply,

According to Canfield's book on page 799; 200,000 to 500,000 should be a short pinion with a spanner and windage knurled with elevation checkered.

500,000 up should be a rounded bar, windage knurled, elevation checkered.

At 472,182 this may be correct?

None the less, thanks for looking and your thoughts.

Regards,

Tom