Top stuff Si. Love the pics.
It's me that waffled on about the last 10m etc.
I've not explained it well. I do think that there will be some dramatic loss in the last 10 metres ... but not all in the last 10 metres. I was saying that if we said we had a gun that shot a spread of 20fps at the muzzle but gave great groups at 40m we'd all believe that. We'd all love less than 10fps spread at the muzzle but we've all had guns that do 20fps at the muzzle but give great long range groups.
We all got excited about the 40 or 50fps at the 55 yard mark and thought that should give a lower poi.
I was saying that at 40m the difference probably wasn't 40fps but only say 20 or 25fps. It will have been less than that at the muzzle and less than that all the way to 40m and only just reached 20fps at 40m. So hence great group at 40m. Now take 40m as the start point ... we have 2 pellets starting at that point that have a 20fps difference and only have to travel 10 more metres to 50m ( 55y ). We wouldn't expect the groups to open up with just a 20fps spread over 10m.
So I did suggest that it should be done indoors and test at different ranges ... say 35 and then 45 yards and see what the differences have opened to there ... and see the groups ... and then test again at 55 yards.
I reckon we will see that the differences are only 20fps or so at about 45 yards and most of that deterioration is in the last bit.
It's been like an optical illusion but with numbers ... we all saw 40fps spread at the 55 yard end and thought 40fps must give a big difference in poi ... but it only just reached 40fps at 55 yards and would have been doing much much less than that through most of the travel.