Just found this:

"SN 1. Cal. 11mm. Dreyse Patent Model/Sample Bolt Action, Mauser 71 cartridge, only bore leed rifled, action sample as Patent Model for British Patent 4198/7, marked "FRANZ VON DREYSE SOMMERDA, GEWEHRSCHLOSS MODEL u LAUF mit ROTATION EINRICHTUNG". Unique factory demonstration piece or patent application model showing the workings of the Dreyse patent action with rifling restricted to a short length immediately before the chamber in the bore leed, the remainder of the barrel being smoothbored to reduce bullet friction in the bore. All metal is in the white with the exception of the trigger and has scattered light brown patina. Mechanics fine and action is crisp. SN 1 on left side of bbl flat. Bbl has only lead rifling with remainder smooth bore. PROVENANCE: Collection of Dr. Geoffrey Sturgess. CONDITION: Antique, good to very good. Wooden portion of stock shows numerous dings and handling marks. 4-53079 DW58"