Bump

Bumping this one to the top. This one now sits at the local museum, the staff is looking for more info on it. Someone suggested this could maybe be wing-attachment. The machine gun is in .303, Any additional info would be appreciated.

P.S. the pistol grip on the photo is not related to this piece

Thank you John for your reply. Maybe it is American but then the gun is probably 30.06 right?, I have not checked the caliber to be sure but he was pretty sure the old man that it is .303 but his memory is not so fresh anymore. I am going to clean it up and look for markings. The sad part about this gun is that it was in good condition but for the past 8 years it has been stored in a leaking shed and all the rust you see is fairly new. He told me every part of the gun worked and was moveable few years ago.

Regards Ice