The cancelled markings (the crossed out ones) are not date markings but rather Unit and rack number markings. As the 1910 Ross Mark III was being issued, these rifles were passed down to other Units for their use, and the receiving unit cancelled the previous number, and placed their own Unit number, and the number of the rifle's position in the rifle rack, (or the number as received and recorded as being on strength for that Unit.)

Camp Valcartier, Quebec, was built in 6 weeks, and had the longest (widest) rifle range in the World, over a mile wide. About 35,000 men were arriving at Valcartier, most of them from different regiments, and while they brought their kit with them, most of the arrivals did not bring rifles. Thus there was a great need for rifles to train these men. This was solved by taking the rifles from Armouries that were within close distance of Valcartier and shipping them to Valcartier for training purposes.

I would say from the position and style of markings, the GGBG marking was originally one of these rifles that was taken from the GGBG Armouries.

Sam Hughes, the Minister of Defence stated that Canadaicon was not going to send Regiments but rather Battalions. So Battalions of approximately 1000 men were formed by combining similar men from various Regiments---for example, men from four or five Cavalry Regiments were formed into a Battalion, and men from Infantry Regiments formed into another Battalion. The First Contingent of the Canadian Expeditionary Force had Battalions, numbered 1 to 17 aboard.

Your rifle has several Battalion markings on it. The top number will be the Battalion Number, and the bottom number under the line is the Rifle rack number. Thus GGBG over 37 is Rifle number 37 of the Governor Generals Body Guards. 51 over 538 is the 51st Battalion, rifle number 538, etc.

It would appear that the 1905 Ross Military Mark II rifles had a varied career at Valcartier. While some of them we see have only the markings of the original First Contingent Battalions, ( 1-17 ), others have numbers all over them, including the left side.

When the USAicon declared war in 1917, New York State wanted 20,000 Ross Rifles to train their troops. The Federal Government grabbed these rifles and then generously let New York State have 10,000 of them back. The Feds also grabbed a lot of the Mosin Nagant rifles that were on hand and were not going to be shipped to Russiaicon because of the Russian Revolution. These were actually property of the Britishicon, who had paid for them but refused to ship them to Russia. These Ross and Mosin Nagant rifles were primarily used to teach Drill to soldiers, rather than shooting.

The Americans were very short of Springfield rifles, and used the British Pattern 14 rifle as a basis for the Model 1917 Enfield. More Enfields went overseas with the AEF than Springfields.
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