MarcAccording to Eugene Myszkowski's book,
Remington Autoloading & Pump-Action Rifles, Remington's production numbers for the Model 6 totaled 36,236 which included three engraved models.
The breakdown by caliber: '06/50.2%, 270/29%, 243/10.3%, 308/7.6%, 6mm/2.9%.
Jerry-that 6mm you have is, indeed, one of just a tad over 1000.