Unsigned dual calibre tap-loader butt reservoir rifle
This rifle was auctioned in December 2017 at Holts Auctioneers in London but didn't make its reserve.
Auction blurb:
"A SCARCE 54/120-BORE PRE-CHARGED PNEUMATIC DUAL CALIBRE STOCK RESERVOIR AIR-RIFLE, UNSIGNED, no visible serial number,
English circa 1840, with re-browned octagonal micro-rifled 30in. barrel with detachable micro-rifled brass full-length insert, dove-tailed blade fore-sight, standing notch rear-sight with two additional folding leaves, border and scroll engraved tap-action receiver, rotating safe and cocking hammer to the right hand side, leather re-covered stock air-reservoir with shotgun butt, guarded trigger, walnut fore-end with horn nose-cap and provision for ramrod (missing) "