What is the difference between a Remington model 8 and Remington Model 81?

Answer 1

The 81 is a improved version of the 8.

Insightful... ;)

It's mostly cosmetic, pistol grip stock, and stock/fore-stock are beefed up. (more wood).

They also added the .300 Savage and dropped the .25 Remington (although I'm not sure initially)

Yes, in the Model 81 the .300 Savage was added and the .25 Remington chambering was dropped when those barrels ran out. Model 8 and model 81 barrels are interchangeable, as are many parts. There are an estimate of about 10 .25 Remington model 81s produced. They might have made a couple more? Either way, .25 Remington chambered model 81 Woodsmasters are collector's items!

Model 81 production years: 1936-1950

Total production: Approximately 55,581

Model 8 production years: 1906-1936

Total production: Approximately 80,600