Could anybody tell me what model of shotgun this is?

[TrebleisMyMiddleName]

Hey, I was looking around in my basement, and I found my (dearly departed) grandfather's shotgun.
It's a Winchester, I know that. (It says Winchester on the stock, so I think it's a safe guess.)
I'm guessing it's a 12-gauge, but I'm not positive, and I'm not really sure how to tell without purchasing some shells and seeing what fits. It's not pump-action, it's got a handle (it's not very big, it's only large enough to fit an index finger around) on the right side of the receiver to chamber each round manually. As for capacity, I'm guessing three to five shells. It's got wooden furniture, and it doesn't have a rear sight, just a small front sight. I'm guessing it was probably made before 2000, since it's not very new-looking, and my grandfather died not long after that.
I'm not getting home again until next weekend, and I wasn't thoughtful enough to grab the serial number, or take a picture (D'oh!) so I hope this is enough for somebody to go on.
Thanks.

[Blackbuck]

Winchester Model 1400 perhaps?

[Novice]

A picture of the shotgun will help a lot, I think.

[TrebleisMyMiddleName]

Winchester Model 1400 perhaps?

No, not quite right.
There's a "button" under the bolt on mine, and I don't see it on the 1400.
Close, though.

[TrebleisMyMiddleName]

Looked on the Wikipedia page, I think it might be a Model 50.

[TrebleisMyMiddleName]

Yeah, the Model 50 looks right.
As a follow-up question, would tactical accessories for the later Winchester models still be compatible with the Model 50, and would I be able to fire the Model 50 using modern shells?

[Blackbuck]

If I were you I'd put a post up on ARFCOM namely in the following sub-forum.

http://www.ar15.com/forums/f_6/1_Shotguns.html

I think you'd get somewhat of a better response over there than here.

~Mark.