Butt plate markings

[Matt K.]

Ok, I asked this question a few years back, but I have a follow on.

On my 1884 TD below the top screw of the butt plate the rifle is marked

2
F
29

Is there a standard marking convention?

Is 29 "29th" regt?

The answer as I remember it, was "no". But based on ID'ed rifles is there some way to make an educated guess (realizing it isn't perfect)?

[Tom Trevor]

2nd infantry [new york??] regular units were NOT allowed to mark their weapons in any way. Company F weapon 29 issued to private Hernando P. fudmutter or someone else.
Second N.Y. served in the Spanish War, quick internet search turned up several links to them.
just my guess.

[Matt K.]

Being a trapdoor, I expect it to be state volunteer unit. I don't think the 29 is a weapon number as there is a 77 stamped into the wood. 77 presumably being the rack number.