Trapdoor carbine ?

[MIL rifle1]

I want to buy a Trapdoor carbine. I think I found one, but I'm not 100% sure. The serial # is in the 440000 range, I think? Can someone tell me what to look for to make sure it's not a cut down? Any help would be greatly appreciated. Thanks.

[lboos]

440000 sn. would be 1888.... A quick way to tell is to put a dime on the end of the barrel, it should be a perfect fit, if the barrel is larger then the dime it's been cut down.