Glad to notice that our pins aren't visible.
The base has been specially machined with a flange resting on the front receiver ring and is soldered...no problem, even with a bigger scope !
Concerning the detachable stock system it's a variation of the take down modification found on the pre-war Mannlicher-Schönauer rifles sold on the English market.
Its application on Mauser actioned repeaters was first used by Westley-Richards before WW1, then by H&H to replace their barrel unscrewing take apart system.
Sorry for my English, it's a quick reply...!

DORLEAC
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