Rifleman, All US M1917's left the various factories with walnut stocks and handguards. I have never seen a WW II era M1917 rebuild, that I thought was authentic,with anything other than a walnut stock. I believe,but have no documentation or proof, that the birch stocks/handguards occasionally seen were of foreign manufacture fitted when the rifles were provided as Lend/Lease or MAP programs. These stocks may then have been imported as surplus and sold commercially,accounting for their showing up on rifles in the US.
i have three distinctly diferent color rifles but i believe they are all walnut , the darkest[P1914 Eddystone] is a case of the finish being very dark on a dark walnut , the midrange [M1917 Winchester] is a nice mellow finish on dark walnut , and the light one [M1917 Remington] is what might look like birch but i believe its just light walnut wood with a very light colored finish
Agreed, Walnut can vary more in color (to the lighter end of the spectrum) than many would suspect. In particular, stocks that have not had layer upon layer of organic preservatives applied to them will be much lighter in color than you might expect.
I have a M1917 stock I obtained from Springfield Sporters that is practically yellow. Not being a tree person, I've no idea what kind of wood it it, but it sure ain't any kind of walnut I've ever seen. It has no markings whatsoever. Given that I bought it three decades ago when M1917 rifles went for a lot less $$ than today, I'd speculate its not a reproduction, but a WW2 replacement. Alas, I'm currently away from meine zeughaus, so can't provide photos.
(And no, MJL, the M1917 I sold you doesn't have a yellow replacement stock I dyed brown with stuff from the bottom of the spittoon. That one was gen-u-wine...or so the guy I got it from told me,)