the parts were received, Dan Coffin of Coffin Gunsmithing started putting the rifle together.
My dream came to reality shortly after being confronted by a couple of Cape buffalo bulls while hunting plains game in South Africa. Immediately upon returning to the States I stopped into Coffin Gunsmithing’s shop in Victor, Montana, where Dan Coffin and I ironed out plans for a brand new custom big-bore Rifle. Ever since 1990 Dan has been in the employment of the country and western singer, Hank Williams, as Hank’s private gunsmith. Recently, however, Dan has been taking on additional work building both bigbores and varmint rifles. He has a tremendous amount of experience constructing bigbores and soon we had the beginnings of a rifle plan on the table. I agreed to do much of the leg work in obtaining component parts, which primarily came from the mail order house of Brownells, while Dan would see to getting the CZ 550 action and the Montana Rifleman barrel ordered.
We felt the CZ stock trigger (left) needed modifying. Our newly revised trigger (right) eliminated the set trigger mechanism and moved the trigger farther back.
The CZ 550 action was going to take a consider amount of work, and Dan indicated he would get started on it as soon as it arrived. The bolt face would need to be opened, the ejection port enlarged, the magazine converted over to a single stack feed and the trigger Modified. The single stack feed was necessary to ensure proper and reliable feeding of the huge .500 cartridges and the trigger modifications would eliminate the set trigger design that CZ seems to be so proud of. Dan would also move the trigger further back, giving it a more pleasing appearance inside the trigger guard. To provide an added degree of support Dan recommended that we add a second lug that would attach to the underside of the barrel. This would provide a little more surface area and strength to guard against stock cracking as a consequence of the expected heavy recoil of the .500.
I normally prefer the appearance of black walnut, but due to the demands placed on the stock by the .500, I decided that a piece of the typically stronger, French walnut might be a better choice. Before long we had a nicely figured, solid, AA-Grade French walnut blank waiting to be roughed in, after which Dan would do the fitting and finish work.
Whenever you try to send a big 570-gr. bullet out the muzzle between 2,300 and 2,400 fps you can, as a consequence, expect a considerable amount of recoil. For this reason I wanted to leave the contour of the barrel heavy, which wound up to be close to one inch in diameter as it met the forearm of the stock. The most common barrel length for a rifle like this is probably 24 inches, but I was looking for a fast handling rifle for those tight spots on dangerous game that no one wants to be faced with, but appreciates being prepared for. A barrel of 22 inches seemed to fit that bill perfectly. In order to provide better overall balance and at the same time reduce the felt recoil, two 1-lb. mercury recoil reducers were placed in the butt stock. This resulted in a terrifically well-balanced rifle that would swing quickly. Eventually the rifle hit the target weight of just under 12 lbs. with scope.
One thing I fear possibly as much as being mauled by a hungry lion or stomped by an angry elephant is the idea of getting hit in the eye with the scope from a caliber like the .500 Jeffery. I have been the recipient of such a blow but from a much smaller caliber and I do not want to repeat that experience, especially if it is the consequence of sending the equivalent of a 1-1/3-oz. fish-ing sinker speeding to its destination. For this reason I took the advice of a close friend and retired South African professional hunter and got the scope away from my eye. We mounted the long eye relief Leupold scope 10 inches out on the barrel and anchored it with a Modified set of Leupold quick detachable QRW mounts.
The wrap-around fleur de lis checkering pattern, complete with ribbons, is a work of art and adds a significant bit of elegance to the overall appearance of the rifle.
A critical point in constructing any custom firearm in either a wildcat caliber, or in this case what some people might consider an obsolete caliber, is ammunition. And in the case of the .500 Jeffery, if you’re going to shoot it, you’re going to load for it. Working with the chamber reamer manufacturer Pacific Tool and Gauge and the custom reloading die shop of Hornady I was able to get the two parties together in order to ensure that the chamber dimensions would match precisely the reloading dies.
Once the metal work was well underway I was able to turn my mind to the finish work. Who would do the stock checkering, a much needed part of any beautiful custom rifle? And did I want any metal engraving done? Eventually it was decided that Pam Wheeler would do the checkering. Pam was well known in the business and over the years has checkered for companies such as Kimber, Cooper, Weatherby, Ljutic and even the famous late custom shotgun maker Tommy Sietz. Pam is exceptionally flexible and has the ability to provide you with virtually any pattern and style you prefer. Before long we had agreed to a moderately fancy ribbon fleur de lis pattern similar to one she had done recently on a friend’s custom .416 Rigby rifle.
Gouse Freelance Firearms Engraving completed the metal engraving project by adding a Cape buffalo on the magazine floor plate.
The .500 Jeffery/
.500 Schuler Controversy
BY JAMES TUCKER
Sifting through the sands of time is a daunting task! In this case, and I do mean case, I’m referring to an eighty-year-old controversy over the cartridges we know today as the .500 Jeffery and the 12.7X70mm (.500 Schuler).
In books and articles that I have read over the last thirty years, most of the controversy seems to be over who originally developed the cartridge. The year 1927 is when Schuler and Jeffery introduced their cartridges to the public. The first mention of August Schuler Waffenfabrik’s new cartridge appeared in a German gun magazine that year. They named and promoted it as the .500 Schuler. It wasn’t until 1940 that RWS renamed it the 12.7x70mm. The records of the firm W. J. Jeffery show that they sold their first .500 in 1927.
While this is of interest to many with a historical outlook, those who build and shoot the Schuler/Jeffery cartridges need to know that they are NOT the same cartridge. They are two separate cartridges although nearly everything in print says they are the same. Having worked on six rifles chambered for the “.500 Jeffery” and been involved with two others, I can tell you that the two cartridges are definitely different.
The important difference between the two cases is the shoulder angle. This is very important because for rimless cartridges, as both of these are, the headspace length is determined by the distance between a point on the shoulder and the base of the cartridge. When the angle of the shoulder is changed, the length of the headspace is also changed. If you put a cartridge with a shorter headspace length into a longer barrel chamber, you instantly create a condition known as “excessive headspace.” This may result in a case rupture and can cause serious damage to the rifle and shooter.
The Jeffery has a longer shoulder angle of roughly 12.5 degrees. The Schuler utilizes a shorter, steeper angle of a bit over 19.5 degrees. The consequence of putting a .500 Jeffery cartridge in a .500 Schuler chamber is that you create excessive headspace. And, conversely, putting a .500 Schuler cartridge in a .500 Jeffery barrel makes it difficult or impossible to close the bolt.
C.I.P. (Commission Internationale Permanente pour l’Epreuve des Armes à Feu Portatives, the European equivalent to SAAMI) standardized the dimensions for the “12.7x70mm (.500 Schuler),” its official name, in 1998. The “500 Jeffery” received C.I.P. approval the following year. Both were slightly revised in 2002. A quick look at the
