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I never heard of a Centennial Model BL-22, either - the "centennial" of what ? (pics ?)
AFAIK, Browning only ever made the standard Grade I BL-22, the Grade II Bl-22, the Grade II Octagon Bl-22 & the Grades I & II Classic Bl-22 (similar to the Grade I & II BL-22, but w/satin-finish stock).
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