Hi Skot,
I've checked it out further
Page 29 of The "National Rail Conditions Of Carriage" States that it is now at the descretion of each company (where it used to be okay under British Rail as long as it was unloaded) . So written permission would be required from each company we will be using if the guns are kept intact. Each company can charge a fee for the gun as well if they wish, so I think it's a good idea to seperate the action from the stock, this renders the gun technically inoperable and as such not a gun, but parts that can be carried without fear of complaint or penalty
M