There has been a claim that WRA "created" the 7.2" spacing in 1917, thus the first "Springfield Marine" bases in 1917. Shown below is a 1910 rifle with a B5 scope with #1 WRA mounts on 7.2" spacing, which means the very early #1 mount is mounted on "Springfield Marine" bases. This is a Marine rifle. As I said before, the WRA scopes on 7.2" spacing existed long before 1917.
Note how prominent the grasshopper spring is in the picture. They are not hard to spot at all. Judge for yourself.
This picture is straight out of Peter Senich's book, Scout-Sniper, which I highly recommend. Senich spent 20 years digging through the same USMC files currently being unearthed at the Archives. Peter Senich has long been considered the ultimate expert of Marine sniper rifles, and justly so.
More to come. Enjoy.
Pre-WWI USMC Scoped Rifle - SN 454040 - page 8 in Senich.jpg