My COW #11 says what you have are 360 Express (2.25-inch) rounds, also known as
the "360 Nitro for Black", or "360 Nitro Express".
The blackpowder rounds show a bullet weight of 134 grains as "standard", though
weights varied from 71 to 215 grains. From the photo, I'd say case length is
2-1/4 inches, though case lengths varied. Another common version was 2-7/16ths
inches, a length favored by such notable designers as Alexander Henry, who
designed a LOT of popular rounds back when. Dates for the rounds are fuzzy, but
some time before 1873.
Nitro loadings saw bullet weights of 190, 200, 250, and 300 grains, possibly
higher in some versions. The Nito rounds date to 1900-1902.
in power, it's close to the 38/55, with a slightly smaller bullet. (Nitro loads
Bertram Brass of Australia still offers brass for it. Your loads are most
likely over 100 years old.
I'm still sniffing around for a guesstimated value, but suffice it to say
they're pretty rare. I wouldn't let loose of them until you have a baseline to
draw from, serious collectors pay a LOT of money for obscure stuff like that.
Those are also known as the 360 Miniature Nitro 2 1/4''.I found some on this website here.They are going for $10 each with holes in the side of the case from where they were on a Display board.I would guess with yours being live rounds they would probally be worth $10-$20 more than that.Hope this helps.
You will have to scroll down the page to find them.
I copied and pasted this from the webpage.
++ 7816 .360 - 2 1/4" Miniature Express, round nose copper tubed lead, 2 stab neck crimp, large flat copper
primer, headstamp KYNOCH '360, from display with 2 holes in one side of case $10.00
7360 .360 - 2 1/4" Miniature Express, round nose lead hollow point with wood peg, copper primer,
headstamp . ELEY . LONDON '360 $18.00