The engraving between Grade-0 and Grade-1 guns tend to cross over a bit depending on the year-period they were made. We have seen some T/A Grade-1 guns that except for the lack of engraved birds, are practically indistinguishable (engraving-wise) from the Grade-2 guns.
Barrel steel, engraving styles, checkering patterns... are usually the best ways to determine the grade of a Parker, but sometimes they are a bit more puzzling.





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Dean mentions the Grade 1 guns that "look like" Grade 2 guns except for the birds. My favorite Grade 1 gun is identical to a Grade 2 except that the circle on the floorplate is empty of engraving. It even has Damascus barrels like just a handful of similar Grade 1 guns in the forty some thousand serial number range.