If it helps at all; trying to shoot the No1 in the standing unsupported like that is very much on the harder end of the shooting difficulty scale. Looks like the range wasn't that long but the target was a tiny little round plate? Pretty tricky.
World War era bolt-actions are long with all the weight out the front by comparison to modern military carbines and the open/notch sights on that variant are, imho, far worse and harder to use than the aperture on a No4 (or indeed most guns that came later) - which you probably realised by comparison to the .22.
Obviously it's only a short clip so I don't know, but if you spent the whole 70 seconds up in the aim, you'll have gotten less steady as time went on, you're only human there's no beating that. That's a standard issue that people run in to when learning and is worst in the standing position. You can get away with it for longer as your stance gets lower, but even then it's usually better to relax and only spend as long aiming as is necessary to get your ducks in a row before firing.
Not massively transferable to airsoft of course, but peeps who can shoot usually at least manage to look a bit better in candid site photog pics I find.