Casey,
I will put up another way to get to that web site. It tells you where to find the mark on every part to see who made them. Try this
http://m1903.com/m1917markings.htm
The rifle is built on a British Enfield pattern and has no connection to the US Springfield. When the Americans entered the war the big gun companies were churning out the .303 P14 Enfield pattern for the British. The British had decided on this new rifle (with new rimless ammunition) to replace the SMLE but the events of 1914 and the failure of Vickers, the main contractor, to produce the required number led to continued SMLE production in UK and reversion of the P14 to .303 and the American contracts.
A big US 1917 investigation made it clear those companies making the British P14 could not convert to producing the standard US Springfield rifle in a short time. The decision was made to just modify the .303 to the standard US 30-06 calibre which could be done quickly because all the main components were already pouring down the production line for the British. So was born the P17 which pumped out until the end of the war and was issued alongside the Springfields to US forces.
Eddystone (a subsidiary of Remington until sold) produced 1,200,000 while Remington and Winchester produced about half a million each. It would appear the million rifles sent to the British 1939/40 were of this stock and 30-06 calibre. From what I have found they armed the Home Guard and often had a red band around the fore stock to indicate .30 calibre because they could easily be confused with the almost identical appearing .303 P14 which was still in use at the same time.
After WW1 the P17 was withdrawn and the US standardised on the Springfield which a large portion of the US forces were still using at the end of WW2.
Lang
PS. The date of your rifle is 1916 - '16. The other number is the proof load and it says "BNP (Barrel Nominal Pressure) 18.5 tons per square inch".