I think all of the 1200/1300 series were 3" mag. I could be wrong but I do believe that they all are.
The 1200/ 1300 series shot gun is a perfectly serviceable shotgun that will give the averarage owner a nice gun to hunt with reliably.
When I was mentioning about it's weakness,my comments were made from what I have read regarding heavy use(almost torture for military/police work) and some of the comments from others on these posts who have law enforcement experience.
My own experience in fixing the 1200 model was people who own guns that did not know the value of proper care and cleaning of a firearm.
Still, the parts are stamped but they are parts such as the lifter, shell stops, and other verious action parts.
I think that the Winchester1200/1300 in the right hands, maintained properly is a very good shotgun for home defense and hunting.
There are better guns such as the (older) Remington 870 models, Browning pumps, Ithaca model 37, Mossberg 590, mind you.
When I say better I mean that maybe 2 genrations worth of use can be had such as we see with a Winchester model '97.
If the gun works well, looks good and is priced right, I say go for it.
I've had a couple of Winchesters, a 1200 and a semi model 140.
I didn't like the fit of the 1200 and sold it .
I could kick myself in the but for letting the 140 go.
That thing could spit lead like nobodys business!