Antique Spencer 1860 rifle - early serial number

[ShootingSean]

Here is my M1860 Spencer rifle 

Markings:
Serial# "1480" located on the upper tang and under the barrel, in front of where the forestock screws in.
"L" stamped on the barrel underneath the largest barrel band, on the left side.
"JWCLAPP" stamped on the butt end of the forestock.
"1" or "|" stamped at the front of the receiver, where the forestock makes contact.
There is NO inspector stamp/mark on the stock.

Barrel length is 72cm or 28 1/3" from the front of the receiver and has 6 grooves/6 lands rifling.
Forestock is 63.85cm or just above 25"
OAL is 119.5cm or 47"

Read somewhere that serial numbers 1000-1550 were used at Gettysburg under Custer - anyone know if this has any basis in reality?
Also, the forestock is a little interesting - it has the letters "JWCLAPP" stamped at the butt end.
All I can find online, is that JW Clapp was a Mississippi lawyer who was part of the Mississippi Secession Convention and also was a Representative in the first Confederate Congress - if this rifle was his at some point, it would add to its history 
I guess this ownership would have to have been post war, as the Spencer was exclusively given to Union members(?).

Any and all info on this weapon is greatly appreciated, so is references to books and online reading about the Spencer rifles! 

[ShootingSean]

[ShootingSean]

...more pictures...

[ShootingSean]

...and more....

[El Supremo]

Thanks for the interesting photo's.
Are my aged eyes really bad or is the photo of the open top of action somehow a reverse image with extractor and its cut on the right and hammer cutout in the frame on the left?
If so, am fascinated how that reversed image was achieved.  Smiles and thanks.
El Supremo/Kevin Tinny

[ShootingSean]

Thanks for the interesting photo's.
Are my aged eyes really bad or is the photo of the open top of action somehow a reverse image with extractor and its cut on the right and hammer cutout in the frame on the left?
If so, am fascinated how that reversed image was achieved.  Smiles and thanks.
El Supremo/Kevin Tinny

Somehow I managed to mirror the image on my phone before uploading 
It is fixed now 

[El Supremo]

Thanks for the info:
Might be best to not do any cleanup until the history is clarified. Smiles and a LIKE.
El Supremo/Kevin Tinny

[Cap'n Redneck]

I trust You are aware of Roy Marcot's book: "Spencer Repeating Firearms" ?
It is THE bible on Spencers...

Fascinating how (and where) Mr. Clapp marked his rifle...not visible from the outside as in most cases, but once you dismantle it; there it is in capital letters.

[Trailrider]

Can't give you any more info, but it is possible the rifle was picked up by Mr. Clapp on the battlefield or taken from a Union prisoner, or, as you said, later. Might check National Archives or Michigan Historical Society to see if they have a list of soldiers with Custer's Michiganders (5th Michigan Volunteer Cavalry???).