Instruction manual for 1970's custom .22 scope...

Question

Dear Sirs:
I recently bought a Bushnell Custom 3x-7x .22 scope from the 1970's. It has the Bullet Drop Compensating feature. I need a manual. How do I sight this little scope in for elevation? There seems to be no way to raise the elevation separate from the BDC feature...

Sincerely:
William Davidson
St Louis Mo

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