Just thought I'd clarify, I don't actually work in law and I never finished qualification. I did however complete first year law at Uni with top marks, which is all you need to be able to understand airsoft/firearms law and advise upon it (once you have the basic skills, it's all research) xD
I did help advise on the predicament of U18's and new players during the construction of the VCRA etc.
I've got quite a few bits to research, but I'll stick this on my list.
From a guess though; as long as it's on private property, which doesn't have public through-ways, isn't massively visible to the public and would in no way pose any risk to law-abiding citizens, and you don't have ANY money or anything else of ANY value changing hands, you can do whatever you want with regards skirmishing (provided you're within the realms of the rest of British law, but it's mostly common sense). That doesn't mean it's as simple as that, what follows are some things you need to consider:
I would advise contacting a variety of people in order to confirm risk. You need to identify footpaths near the site, you need to establish a good perimeter fence to prevent people wandering on and catch BBs leaving the area (even if someone is illegally tresspassing, you are NOT indemnified if you shoot and blind them; just shooting them may be enough to see you charged for common assault, or possibly assault with a weapon), you probably wouldn't go wrong informing neighbours and the local police force etc of your intentions, just so they all know if they see/are told about a bunch of nutters running round with guns on X property, they don't send CO19 down to check you out (cause they'll do it wth you at the business end of a G36). Put up signs around your perimeter fence that clearly warn potential tresspassers; Ask your local police if they agree that this is a good idea, and how to word it. You also want to check the deed to the land, make sure there are no restrictions on the building of obstacles etc and the general use of the land (this applies even if you're simply a hobbyist, but it is unlikely you'll find any unreasonable restrictions.
Always assume professional practice; eye protection, full face gear for younger players, don't let people in derelict structures etc. Just because it's a casual game with friends and no money is changing hands, doesn't mean you're safe from a lawsuit if someone breaks a bone or it blinded etc. The law does not recognise a mutual friendship as defense from the tort of neglect (causing injury to another through your own neglectful behaviour). I don't quite think you could legally get people to sign a waiver promising not to sue.
Also, if a BB leaves your property and hits another, even if it flies through the perimeter fence completely by accident, the firer is still liable, or in this case, being as it'd be hard to find who fired the pellet, probably whoever was responsible for the property.
Honestly speaking, people have little "BB Wars" on youtube all the time, we've all seen it, and often they're fine, some even illegaly use public land. Most do not get into any trouble, however, those that do will probably find it changes their lives significantly for the worse for a long time. My honest advice is that with all the problems of law and the potential risks etc, you'd be far better simply finding somewhere to pay to play; all you do is turn up and everything is taken care of.
I'll do some proper research in the next 7 days and confirm/modify the above to be accurate with current UK law.
Where are you located so that I can check local bylaws?
