In England? Going thru England with a firearm it's my understanding was impossible. Now if you are setting up for match. You have people picking items up for you.That's possible a different story, but just travel through there on your way to Africa was a different story. That was 2018. So I looked it up and it appears rules have changed.
Yeah it's been a minute since then, maybe things have gotten better since your last experience.....We all flew into London Heathrow with our firearms and had them in our possession the entire time. The only thing handled by other folks was the ammo that we shipped two months prior. We also flew with the max limit of ammo which is 5kg or about 11lbs.