I had originally intended to use bullets for the .505 Gibbs with my cartridge, but learned too late that the Gibbs cartridge was propriatary and the componants not available. Barnes did make a few, using copper tubing for jackets. John Buhmiller used to say that Barnes solids made good soft points.
Fortunately, i was able to locate a supply of Kynoch .500 NE 570 grain solids, so I changed my ambition to replicating .500 NE ballistics instead of .505 Gibbs. At first I had the .510" NE bullets turned down to .505" in diameter, but then discovered that the bullets could be swaged down using bullet sizing dies.
Eventually I gave even that up, when I found that, given enough neck clearance, the .510" bullets could be fired unaltered with no ill effects.
I was able to propel the NE bullets at 2150 fps with ease, and that was the load I used in Africa. I loaded primarily solids. I never used what few soft point bullets I took with me. I did take some 600 grain Barnes "solid" loads and tried one out on a wildebeest at 100 yards. The animal went down at the shot, got up and took a step or two, then went down for good. The bullet had shattered on the shoulder blade, but had the desired effect despite its theoretical failure.
I later had an identical rifle made using a .510" groove diameter barrel. It performed well on the range, but I never took it to Africa. It has found a home with
Buckstix.
Designing a cartridge and bringing it to fruition in Africa did give me a sense of achievement. I know John Buhmiller had done the same with his alteration of the full length .378 Weatherby cartridge to take .458" and .510" diameter bullets, and it gives me a lot of satisfaction to be in such illustrious company.
View attachment 486645