while not the prettiest nor 100 percent correct (rear sight is a rifle sight).  I do believe it is an honest carbine with a 22" barrel and not a cut down.  It falls in the middle of the 2nd block as shown in Mallory 1st Ed and Brophy books.  most of the items I think are correct as near as I can tell by reading and comparing (gate and side plate look correct to me)  the patina on every thing except that rifle sight appears evenly worn.  Cartouche are not readable just can tell there are out lines and maybe some wishful thinking on my part.

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