Dear Djordje,

Thank you for your request. The presented object is a modified Peabody Martini Creedmore Mid range rifle. Remarkable there are no comparable pieces mentioned in databases or similar reference books. As the customer suggested this could be a modified prototype. This needs to be verified with archival research. It is difficult to find an estimate for such a unique piece also because of the medium condition.
This piece is in medium condition and there are little damages visible.
An base auction estimation would be between 300 to 600 USD.
This estimation is based on actual recent past recorded auction sales of comparables. Retail "asking prices" can be higher and vary.

With best regards,
Georg

Peabody-Martini Mid-Range Creedmoor Single Shot Target Rifle Cal. 44-100
Serial Number: 376
Description: Manufactured circa 1875 to the 1880s. This Martini Creedmoor Target Rifle was manufactured by the Providence Tool Company of Providence, Rhode Island. Several variations of this rifle were manufactured and it is estimated that less than a thousand of all types of sporting models were produced. The receiver is lightly engraved in gothic script, with "Creedmoor/Mid Range" on the left side and "Peabody & Martini Patents" on the right side.
Finish: Blued steel.
Condition: Poor. Barrel was been cut/shortened. Butt stock and forearm have been removed. Rifle has been remade into a pistol. The markings are clear. Working condition of the firearm is unknown.
Extra Notes: The BATFE has made it very clear that once a receiver is built into a rifle, whether by a factory or by you, it is always a rifle and converting it to a pistol is illegal. I would advise caution selling this firearm in the future.