Mosin Nagant: is there any significance to a missing "r" after the date?

[jjjxlr8]

Here's some from #74

Notice how light the mark is on the 1940 example.


1937 with (refurbed)


1938 without (non-refurbed)


1939 with (refurb)


1940 with (non-refurbed)


another 1940 with (refurbed)


1941 without (nazi refurb)


1942 with (refurbed)