actually, this just came through from GS Custom.

I do the R&D for GS Custom Bullets.

When it comes to double rifles, especially older ones, I would not shoot anything other than jacketed lead and true drive band bullets in them. I have been gunsmithing since 1979 and have seen my share of trouble (expensive) with double rifles and hard bullets. According to Sabi Rifles, who are the appointed agents for Krieghoff doubles, they will not honour their guarantee if the gun was fired with bronze monometal bullets.

A jacketed lead bullet requires around 1200 pounds (roughly 10 000 psi on the base of the bullet) to get started through the throat of a barrel. A conventional copper monometal bullet takes around 1500 pounds and a drive band bullet will get going at less than 400 pounds depending on calibre. I do not have the numbers for bronze solids or grooved copper bullets and I am not set up to do a test of this nature at the moment.

GSCustom.co.za

Sound conclusive?