What is the difference between Winchester defender 1200 1300 1400?

Answer 1

A couple minor differences in interchangeable parts, but nothing major.

Essentially, the 1200 was built by Winchester/Olin from 1964 through 1980. In 1981 (when the 1300 was introduced), Winchester Firearms manufacturing was taken over by U.S. Repeating Arms Company, continuing through the closure of the New Haven plant in 2007. There are some minor detail differences, such as how the slide bars attach to the bolt, but that's about it. The 1300 is pretty much a copy of the Winchester/Olin design. With very few exceptions (principally internal -- nothing to do with mag tubes, barrels, or furniture) parts and stocks are nearly 100% interchangeable.

Also, if it matters, the 1300 & "1300 Defender" (no longer made) will shoot up to 3" magnum shells, where as the 1200 will only shoot (up to) 2 3/4" shells.

The Winchester 1400 is pretty much a semi-auto version of the 1200 (and not a very reliable semi-auto in the author's experience).

My late model 1200 takes 2 3/4" or 3" magnum shells.