Model 2400 shotgun
Winchester made an autoloading shotgun with the 2400 designation back in the 1960s and later. The Model 1400 was basically the same model, but a bit more deluxe. The 2400 was the "plain Jane".
Look at the bolt inside the receiver. There is a short round section at the front of the bolt that rotates. It should have multiple locking lugs (four I think) on it that fit into the barrel. The receiver is an alloy. The model 1200 and 2200 are the pump action brothers of the 2400.
Try Western Gun Parts in Edmonton, Alberta.
These shotguns were discontinued years ago. Winchester also made some for Sears with a Sears designation on them. Not sure on the 1400 or 2400, but the pump gun was the Sears 200.
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