TW,
The rear trigger does not set the front trigger.
I have tried it in any combination possible, back and forth.
It seems that it is a modern tribarreled german gun although made in the 30's, like Geno said. The only puzzle remaining is the choke arrangement.
DGJ of Summer '07 has an article about a Funk flintendrilling with similar trigger/choke combination, but is a toplever and a tang safety. From the article I understood that the RT fires both RB and UB without any other selector operation. The original chokes according to Col. Fred Ball, the owner, were all full. He opened them to RB/IC, UB/Mod, LB/Full in a logical sequence.
