16 | WINCHESTERCOLLECTOR.ORG • Summer 2021 2. Receiver frames that were factory drilled and tapped for peep sights. This change took place beginning in early 1947 and was completed by early 1948, in the 24300–26000 serial number range. Receiver frames were available with the drilled and tapped peep sight holes on special order from the beginning of production, but they must be carefully examined to determine if the holes are original factory work. Drilled and tapped receiver frame Non-drilled and tapped receiver frame 3. Checkered (knurled) hammers versus serrated hammers. This change took place in 1948, very shortly after the previous change. The noted serial number range is 25600–26600. 4. The pistol grip cap on the Special Rifle was changed from the hard black rubber with the Winchester logo to a blued steel cap late in production, somewhere near serial number 42650 (1953). Interestingly, both the hard rubber and the steel grip caps were randomly used until the end of production. This is another case of Winchester not wasting any usable parts.