Odd US Springfield Armory made M1917 Bolo Knife...what sorcery is this?

[MilitariaOne]

Greetings all,

I do hope Santa has been good to you today. He brought me an odd Springfield Armory's made M1917 Bolo Knife with what appears to be a muzzle ring. At first, I assumed it was a leftover cross guard for an US M1915 Bolo Bayonet,which had been used to assemble this knife. Yet, the cross guard in question is too thin for it to be one of those (compare it to the Plumb's manufactured M1917 variant in the image) and longer than a normal M1917's. I would assume the SA's cross guard was a left over of sorts, but not sure exactly from what project. In any case, it was a nice variation, which I had not viewed or heard of before and as such, worthy of sharing with all.

Have a Merry ,

V/r Lance

P.S. The muzzle ring's interior diameter is 15mm, which is the same size as an M1905 bayonet's muzzle ring.

Double click on image to enlarge.

[Chopperman]

Merry Christmas Lance.
That's the first one I have ever see with a muzzle ring.