You can acquire guns, gun parts, and ammunition quite easily in the UK, and entirely legally. You need to hold a suitable licence, which isn't expensive and is

You can acquire guns, gun parts, and ammunition quite easily in the UK, and entirely legally. You need to hold a suitable licence, which isn't expensive and is mostly an exercise in proving to the police that you're not a violent psychopath who's likely to run up to people in cars and shoot them in the face.