Rifle cal. .30-06
"Manufactured by Remington Arms, Ilion, New York"
Almost three million made from 1917 to early 1919, by Winchester Repeating Arms, Remington Arms, and Remington's subsidiary Eddystone Locomotive and Steel factory. This specific example was rebuilt at least once (at Rock Island Armory - big RIA stamp on left stock by receiver, just over and almost obliterating the correct 1918 original stamp). The barrel is a correct 1918 Remington, so is likely original as well. But other small bits have an E for Eddystone or W for Winchester. I believe some parts of that bolt should be blued, rather than all-polished as this one is? ...Not sure about that.
BACKGROUND: From 1915 to 1917, the British had contracted with Winchester Repeating Arms, Remington Arms, and Remington's subsidiary Eddystone to build and supply, with bayonets, the new British design "Pattern 1914," (or P14) bolt action rifle in calibre .303 British. The British continued to produce their 1903 designed Enfield "Short Magazine Lee Enfield" (SMLE) Nr1 Mark III* domestically, but realized their output could never match the expanding armed forces. Prior to August 1914, the British had planned to build their new P14 rifle in their newly approved remarkably far-thinking calibre .276, and gradually phase in the rifles and ammunition to replace all the SMLEs (cal. .303 British) in front-line units, including taking over production of the new rifle by British arms builders as well. However, the opening salvos of the First World War in 1914 changed all those plans. The new calibre was scrapped as impossible to impliment under the time and logistics constraints of fighting a war, requiring millions of rifles and billions of rounds of ammunition. So they told Winchester, Remington, and Eddystone to open the production lines, but maintain the calibre in synchronization with other British firearms at .303 British.
British contracts ended in 1917, by which time British domestic SMLE production had increased sufficiently for the UK to discontinue all P14 production. The US entered the war in April 1917, and instantly created an army of millions, with more coming behind them, but with only a few thousands of US Model of 1903 ("Springfield Rifle"), the standard US shoulder firearm, available, even with maximum production rates at the two US armories at Springfield and Rock Island (Illinois). So the US told Winchester, Remington, and Eddystone to re-open their "Enfield" production lines, but maintain the calibre in synchronization with other US firearms at .30-06 ("thirty ought six"). And likewise continue bayonet production at the same levels.
One unintended benefit of the .30-06 version, was that, since the magazine well was designed and sized within the receiver to fit five .303 British cartridges, and since the .303 British cartridge has a fatter, wider rim, the resulting magazine well in the US Model of 1917 will stack up six of the slimmer, trimmer .30-06 ("rimless") cartridges, ...although all stripper clips provide only five rounds per clip, and few owners/shooters of the M1917 are aware of the magazine bonus. ...Can't load more than five rounds anyway for hunting in most states.
And because it's derived directly from an Enfield design, this rifle is often referred to as the US Enfield. An unaccepted and erroneous reference is to call this rifle a "P17." Such a designation never existed, since the British were the only ones who used the P for Pattern abbreviation style, and they had no Pattern 17. The US designation is US Model of 1917. The action is still highly sought after as one of the strongest bolt actions ever produced, and lending ideally to modifications into sporter rifles of whatever custom calibre is desired.
This bayonet (ABOVE, and also in pictures at top) is a 1918 Winchester, but the scabbard (way up above; it's either a 1918 or 1919) is by another subcontractor still. Although appearing at first glance to be identical, the M1917 bayonet is not interchangeable with the US Springfield Model of 1903 or 03A3, since on the M1917, there is a greater distance (separation) between the muzzle and the bayonet handle, i.e., the bayonet lug, which is an integral machined component of the front barrel band, is lower from the barrel than on the M1903.
Here's a target at 200 yards, from a sandbag/bench rest, using "Lake City" military surplus M2 ball ammo: