Great writeup and photos.
The Win PowerPoint 40gn HP definitely performed better than the rest by quite a large margin. However, you seem to have mixed up the Win PowerPoint 42 gn with the Winchester 555 36grn HP Segmented - see number 6 in the ammo list and number 5 in the results test.
Couple of questions:
What scope is on your Weihrauch HW60J?
Have you compared the supersonic results with subsonic ammo?
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