a friend bought a bavarian M 1869 Werder Blitzgewehr / ligthning rifle that was sporterized between 1888 and 1914 into a hunting rifle. if you don't know it:

https://www.youtube.com/watch?v=npzAhVtAoQM

https://www.youtube.com/watch?v=gOd_XTrLPOw

its called the best rifle of the franco - prussian war of 1870/71 and for some time people were thinking it became the new german breechloader after the war but it lost against the mauser 71, btw the mauser brothers hate it because of its complicated mechanism. original in 11,5x50R Werder most of the rifles were rechambered for the 11,15x60r after 1873 what was easy because the Mauser cartridge is a lengthended Werder cartridge. This rifle here got a new barrel sometimes for the 10x47R, one of the mauser case "wildcats".

he visit me with his new rifle because need help with ammo.

the rifle had a ramrod maybe for get sticking cases out. looks like the original is missing and someone made a new one from bamboo

he got 30 cases made from 11,15x60R brass and some 10,3 mm 278 grains bullets( maybe for the swiss vetterli)
it have a real polygonal rifling

slug the barrel with a .45 bullet, 9,5 mm from edge to edge, 10,0 mm from corner to corner

there came a wooden grip with the rifle and there is a rectangular hole in the stock where someone glued a piece of oak wood into. the rear of the wood grip would fit into this old hole

situation looks unclear but maybe I find a solution for the grip

thats how this works

he got 30 cases, looks like the former owner use something like a 41 mag die for neck sizing but it was done very crude.when sizing the neck with this tool it became 10,3 mm inside. this is maybe the reason for the oversized bullet.they simply fit into the brass after sizing with what he had. he shot smokless powder, btw, we try to get the loading data from him.

my 41 mag softpoint resized to .407( .401 WSL) fit perfect into the brass

the new owner of the rifle will invest into a custom die set, I recommend ch4d.
for me its the first time to deal with a polygonal blackpowder rifle. which bullet diameter is the best? 10,0 mm? a mould for 10 mm auto will be available.