When I set my heart on a .505 back in the 60's, I reviewed what was available and decided that trying to make a .505 Gibbs work through a P-14/M1917 Enfield action was just going to be too difficult, aside from the fact that componants were practically impossible to get and Berdan primed if you did find them.

My solution, after conferring with John Buhmiller, who was in a position to know, was to shorten the easily available .460 Weatherby case to 2.5" and to neck the resulting case to .505, creating a case with a slight shoulder to ease feeding, which held about 90 grains of powder to the base of the bullet and a cartridge which would feed through a conventional length action without modification to the magazine.

The conventional length action I chose was a P-14 Enfield, suitably modified, and equipped with a Lyman 48 receiver sight and Sourdough front sight on a Williams ramp. John Buhmeller supplied the barrel.

As it turned out, no decent .505 bullets were available. (.505 was then a propriatary cartridge, with no componants available to "the trade".) John Buhmiller opined that Barnes solids made good soft points. I wanted something more substantial.

I was able to come up with some 570 grain Kynoch solids meant for the .500 NE and modify them for my purposes. I achieved 2150 fps with no signs of pressure, using 90 grains of 4064, and the rounds fed perfectly, using both jacketed and cast bullets.

Three elephants, five buffalo and a black rhino have fallen to this rifle, and I would be happy to use it on any of those kinds of animals again, if the opportunity presented itself.

The fact is that both the .505 Gibbs and the .500 NE have far too much case capacity for the performance they produce, and since speeding up the bullets would serve no useful purpose, reducing the case capacity does.

That said, I presently have a .505 Gibbs on order, as much a tribute to the Hoffman Arms Company as anything else. I will not be using a P-14 action, however.