Is there any doubt with this one?.

[Gingercat]

I have a SMLE that was proofed at Birmingham at the end of last year (came back just before Christmas) and I'd confirm that the font size is smaller than on your rifle. The bolthead does however have a definite, if feint, crown over BNP stamp, rather than 'dimples'.

Some of the lighter struck 'London' proof marks, often appear more of a 'dimple' to my eyes...

Looks a nice rifle. I was surprised at the 'Y' prefix on the serial number. I didn't think (from Stratton's book) that they'd manufactured that many in 1914. My own 1914 Enfield has a 'J' prefix.

All the best

Mike