I’ve noticed that on my dual-channel D4v2 (219b emitters) the head spring is unusually thin and flimsy compared to my other D4v2s I’ve got in the past 2 years (all single channel)
It used to be a brass pill there on the same pad instead of the narrow spring but then you saw some guys on Reddit complaining that their flashlight cuts power when it is strongly set on it’s tail on the table, basically due to the shock the battery was disconnecting.
Since BeCu is not a strong material as a steel spring is you cannot expect much strong force from it, especially with the wire being thinner than the wider BeCu springs.