Quote Originally Posted by Ax.303 View Post
28 in. is right for a full length barrel.

G 879 is the serial No., manufactured in 1905.

You might be a bit surprised, the bores on Mk I and early Mk IIs are usually quite tight.
I'd like to slug it, but I don't have a suitable dowel handy at the moment.

Quote Originally Posted by boltaction View Post
And your mainspring is in three pieces. This example of yours is an early one, but has been sporterized. Is there anything stamped into the wood of the right hand side of the stock? Ross factory crest in a roundel, date or serial number?
The firing pin spring is split in two, but I think there should be a two-piece spring arrangement with the smallest spring fitting inside the cocking piece. I could well be mistaken.

No, sadly it's blank. Nothing at all. It may have been sanded away and refinished when the stock was cut back.