The 375 Oryxx came about as a result of my love for exotic calibers. I started playing with the idea of a wildcat at the end of 1998, but time and cash constrains prevented the fulfillment of my dream to design, own and shoot my own wildcat. I suppose the enforced time delay had it's advantages as I used the time to study all the related material I could lay my hands on. In 2001 all my ducks were finally swimming in a row (money, time and opportunity) and a friend of mine, Tommie Calldo, who went to work in the USA agreed to order the chamber reamers for me.
I have to say the service from Clymer was top notch, and fortunately for my friend, he was not jailed for bringing the reamers, on his person, through the airports. By the time he landed back in South Africa, I had the barrel and action ready and waiting just for the chamber reamer and headspace gauge he had with him. For the action I chose a CZ ZKK 602, and a 29" Lyttelton hammer forged barrel with a heavy profile, and I had 8 flutes cut into the barrel.. The synthetic stock is from a company called Armtec Stocks, and they have build me a custom synthetic stock. The stock is a thumbhole stock with a pistol grip that is nearly at right angles to the stock. Excellent for shooting from the prone position. The for end is wide and flat-bottomed for stability from a bench rest. The action is glass bedded, and the barrel is free floated forward of the knox form - the front end of the knox form is also the point of balance for the barreled action.
here is a nice picture of the action on the finished rifle.
I had a wooden stock laying around, and with my trigger finger having an uncontrollably itchy feeling that just would not go away, I start the most difficult part of the project, obtaining cases. I finally had to ask the agent for Bertram brass in South Africa to import some 505 Gibbs cases for me. I had no reloading dies to start with but between the +/_ 30 other sets I own, I eventually managed to make a case fit into the chamber. I used 6 or 7 different dies to for the makeshift case, ranging from .455 Webley to 7mm Rem mag. Needless to say I lost a lot of the not so cheap cases in my efforts, but I did end up with 11 out of the 20 cases still in one piece. After fire forming, I was quite impressed with my efforts, and immediately loaded a case with 100grains of Somchem S385 propellant behind a 300grain Hornady bullet to test fire. At this point there was no science involved, so I left the crony safely out of the picture while I aimed along the barrel to get the bullet in the earth backstop.
For me everything came together perfectly in this rifle. I cant wait to shoot it!!!
After the satisfying bang had ceased to echo against the mountain and the ear to ear smile had subsided ( a little) , I inspected the fired case and found the primer showed very low pressure. Now that I have found my start load by shear luck, I can work up to a more substantial load. My original goal was 3300fps with a 300grain bullet, and initial signs show that I might be able to achieve the excepted velocity without to much trouble. However the cartridge is still very much in the development stage, and only time will tell if 3300fps will be reached safely. The photos of the Oryxx cartridge is with a 297 grain GS Custom low drag bullet, and I intend to do my utmost to get the best velocity and accuracy with the GS bullet.
The business end of things.
In the meantime 408 Cheytac cases has become available, and they certainly make forming cases for the Oryxx very simple. I had a head stamp bunter made, and the my cases are now stamped with the correct head stamp. Special thanks to Will Reuter of the RSA cartridge collectors association for helping me in that regard.
The Oryxx is named after the Gemsbuck (oryx gazella). Gemsbuck have adapted very well to the arid, semi, and desert regions of Southern Africa. These areas are very open, and long shots are often required. As the name indicate, the cartridge was designed with long range shooting in mind and is maybe less suited for dangerous game. I certainly do not claim the Oryxx to be anything revolutionary, evolutionary or even superior to any caliber currently in use. What it is, is my own personal cartridge that gives me a lot of satisfaction to own and shoot.
This is the Lynx 16x42 scope I had choosen for the Oryxx.
P.S. No doubt somebody will look at the specs and say I copied the 408 Cheytac. At the time I designed the Oryxx, I was unaware of the 408 and certainly did not copy it. The 408 was designed by very smart people using complicated calculations. The 408 is designed more as a military cartridge and in my humble opinion an excellent cartridge for that purpose.