The magazine held ten cartridges, and was loaded through a slot in the right side of the butt stock.

[3] The self-loading feature of the Model 1903/Model 63 was accomplished by use of a simple blow-back operated mechanism.

This mechanism was redesigned for the Model 63 to allow it to fire the .22 Long Rifle cartridge, which by then had become much more popular.

In modern times, it is more appropriately referred to as a semi-automatic rifle since the loading mechanism required the trigger to be pulled for each shot.

[5] The Model 63, introduced in 1933, was chambered for the popular and widely available .22 Long Rifle cartridge.

About 175,000 Model 63 rifles were manufactured, with the last 10,000 having grooved receiver tops for scope mounting.