870 Express Super Magnum - MFG Numbers and Barrel Change

[AUShooter2003]

Thinking about buying an 870 express super mag 12ga. I have two questions.

1) Where is the manufacturer's (MFG) number on an 870 express super mag? Is MFG number the same as serial number? Looked at a super mag at wal mart. Wanted to find MFG number to verify that it was the same gun I looked at on their website.

2) Looked at the super mag manual in the "Barrel Interchangability" section and it states, "All Model 870™ 12-gauge barrels are interchangeable without adjustment, except the Model 870 12-gauge Super Magnum™ and Model 870 12-gauge Special Field." Anybody know what kind of adjustment is needed for the super mag? How hard is it to change the barrel? Saw a video of a barrel change on a regular 870 express...looked pretty simple. Anybody have a link to a video showing a super mag barrel swap?

Thanks

[Virginian]

Manufacturer's number will be on the box, but not on the gun. Only the serial number will be on the gun.
The Super-Mag and Special Field barrels are not interchangable without adjustment, and there are no adjustments.
On the Special Field barrels, the distance from the receiver to the forward barrel support ring is different, so they will not fit. I am not sure of the specific differences between the Super Mags and the rest of them. Regular barrels may fit on a Super Mag, but not vice versa, but I am not at all sure of that.

[AUShooter2003]

Thanks. I get the MFG # (look on the box). I guess I misinterpretted the manual on barrel interchangability. I thought it meant that even if you were swapping out a super mag barrel for another super mag barrel on a super mag receiver, you would still have to make an adjustment. Based on your post, I now understand that it meant that an adjustment would be necessary for putting a regular 870 express, magnum or wingmaster barrel on a super mag receiver. Is that right?

Thanks.

[Virginian]

No. There are no adjustments that I know of. You can swap all the 2-3/4" and 3" non Special Field barrels into any non Super receiver. 3" may not eject properly from a 2-3/4" receiver, but they fit just fine.
I think you can put a regular barrel on a Super receiver, but not vice versa, but I am not positive. Then again the Super barrel may fit but not eject a 3-1/2" shell, but I do not know.
The barrel(s) either fit, or they don't. That is what they mean by fits without adjustment.