Why doesn't your friend ask Holland & Holland about the advisability and cost of such an operation. I'm sure they will give him good advice. When your friend hears what the cost will be, I think he may reconsider. When you consider that the Royal Grade double rifle presently starts at 99,000 pounds, you may get a rough idea of what the extra barrel set would cost.

When you consider that a Krieghoff Big Five Classic costs $12,995 for the basic gun, and a set of double rifle interchangeable barrels in Big Five calibers costs $9350, you can see the problem.

To take full advantage of .416 accuracy and ballistics IMHO a scope is needed. A scope mounted H&H Royal is sacrilige. I believe a perfectly good .416 Rigby magazine rifle with scope can be had for a fraction of the cost of a new H&H barrel set, and a truly fine .416 Rigby magazine rifle can be had for the price of a second set of Krieghoff barrels.