I own a few Winchester Model 12’s and one Model 42. I was looking at the right sight of the receivers and noticed the Model 42 has two screws. There are none on the Model 12’s. Can anyone identify why the difference. See photos.

Thanks in advance

The two designs are different and were developed by different people at different times. While there are some similarities, the fact remains that the 42 just isn’t a small version of the model 12. There is speculation that a model 12 .410 was actually built (a prototype), but, of course never put into production.

https://www.shotgunworld.com/bbs/viewto ... 7&start=20

https://www.shotgunworld.com/bbs/viewto ... 0&t=271456

https://www.shotgunworld.com/bbs/viewto ... 2&t=340467

Some light reading re the M-12 .410s. Distillation: factory made four bbl assemblies, some/all were later built up into complete guns outside WW. Possible some conversions were made as well.

The two screws on side of the Model 42 are used if it is necessary to fully disassemble the action innards. Quite convenient to my way of thinking. The model 12 only has the one behind trigger guard to remove. Also very convenient.

As to the why question ,there is considerable machining required inside the receiver and a removable plate for access in the narrower receiver would be my guess.

Bobcat