You have seen it on facebook (everyone welcome to joint he group), its .177!
https://www.facebook.com/media/set/?...8077186&type=3

And here is the youtube clip, great accents:
https://www.youtube.com/watch?v=REtUX7cV8dc&t=57s
Output is kinda lousy, compared to my Seniors/Premiers.However on par with most of the MK1’s