Originally Posted by
Josie & John
Hi Mick,
There were 4 types of Britannia rearsight:
Very early models, which transitioned from the 1902 Patent Cox model and Britannia had a fixed rearsight.
Rifles numbered up to approximately the 600 mark had a folding leaf and fixed leaf.
Rifles numbered from the low 600s to around SN 1200 had the sprung leaf, which is the one you enquired about.
By SN 1200 and up to the end of production, the sea saw sight was fitted.
The highest SN I know of is your old .25 example: 3403, which currently resides in my humble collection.
Hope that helps.
John