Hahnvierling, Venus Waffenwerken in Zella Sankt-Blasii
2 barrels 20/70 over two barrels in 6,5x58R
nitro proofed in 1913, 66 cm long barrels and the weight is around 4 kg
http://egun.de/market/item.php?id=4622969

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Hahnbüchsflinte I. Novotny in Prague
left barrel 16/65, right barrel cirka 11,3mm for blackpowder
http://egun.de/market/item.php?id=4622820

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Hahnschienendrillig or Waldläufer 410 and 5.6x35R-Hornet
unclear if this is the 22 Hornet or the older and original 5,6x35R Vierling cartridge
this Drilling was made before WW 1 so the Hensoldt Diasta 4x32 scope was coming much later.

http://egun.de/market/item.php?id=4633781