Handloading the .500 JRH
In 2006, I was privileged to meet gunsmith Jack Huntington on a bison hunt, where he would be testing his new .500 JRH cartridge. The purpose of the .500 JRH, according to Jack, was to create a powerful rimmed .50 cal handgun cartridge that would fit in standard sized Ruger, Magnum Research, and Freedom Arms revolvers, but also be easy to obtain or make brass for. While the .500 Linebaugh had been around for several years at the time, it was strictly a custom proposition. Due to the larger dimensions (by about 0.030” at the base and over 0.050” at the rim) the .500 Linebaugh was not the best choice in Freedom Arms revolvers, and making brass from .348 Win cases required extra steps not typically done by the average handloader. .348 Winchester brass was never widely available and also requires neck reaming after forming and trimming. In addition, at that time dies for the .500 Linebaugh would have been an expensive custom proposition. None of these obstacles are insurmountable for the very serious enthusiast, but they all combine to limit the market appeal. Big bore revolver enthusiasts owe a debt of gratitude to the .500 Linebaugh, even if they can’t afford to own or feed one.
Jack and I hit it off well and after I half-jokingly volunteered to shoot up some of his bullets at my bison, he quickly accepted. No turning back now! This was a unique opportunity to be one of the first people to take game with the JRH cartridge, and as far as I know, the first person to use the “light” 440gr. / 950fps load from Buffalo Bore. The “light” loads worked very well indeed and demonstrated that terminal effects did not depend entirely on maximum velocity. Needless to say I was hooked and ended up owning Jack’s test gun, a Magnum Research revolver from their custom shop with a 6.5” barrel.
The JRH cartridge is based on the .500 S&W case shortened by 0.2” to 1.4.” For custom Freedom Arms guns, depending on who did the work, the rim diameter may need to be reduced to 1.545,” although the Magnum Research gun will accept either rim diameter. Thus, should it become necessary to make cases from .500 S&W brass, all that will be required is to trim the case back, and possibly modify the rims for Freedom Arms guns. This avoids the chores of forming and neck reaming for the Linebaugh cartridge. Although brass for the .500 Linebaugh (and dies) are now available, this was not always so and the Linebaugh cartridge remains a custom proposition as far as getting a firearm chambered in it, as of this writing.
There is another useful artifact of the JRH being based on the S&W. Due to the popularity of the S&W round, as well as other production .50 cal handgun cartridges such as the .50 AE, there are many bullets available for the JRH. The bore size difference of the JRH and the Linebaugh (0.500” vs 0.510”) is inconsequential in the hunting fields, but more bullet choices are better for the reloader! And last, .500 JRH ammo has been available in the past from Buffalo Bore, http://www.buffalobore.com/ and currently by Grizzly Cartridge Company, http://www.grizzlycartridge.com/ Part II will cover modifications to reloading equipment, but the handloader can get started with a set of .500 S&W dies withe the seating die shortened by 0.2," an appropriate shellholder, and primers, powder, bullets, and brass.
On to the actual data. First, the disclaimers. If you are new to reloading, this may not be the best place to start. All of the loads functioned perfectly in the test gun. Velocities are from a 6.5” barrel. Pressures are unknown, but cases fall from the chamber with no effort. Brass was from the first production run and case capacity is exactly 55 grains of water to the case mouth. Primers were all Winchester Large Pistol, NOT rifle primers. I have never used a rifle primer in a .500 JRH load yet and don’t intend to, absent new information that would indicate problems. The Magnum Research gun has no trouble setting off large pistol primers, even though the primer pockets in the brass are cut for large rifle. Likewise, I have never had a pierced primer or other indications that pistol primers would cause problems. Jack Huntington favors CCI Large Pistol Magnum primers in the cartridge, FYI, and feels that rifle primers cause dangerous pressures. All loads were tested in new, unfired brass.
When handloading, it is a good rule to work from known loads and combinations of components, before starting into unknowns (if at all possible). Change one variable at a time. Since this was a new cartridge for which no pressure tested data was available, I just asked Jack for suggestions on starting loads that would be similar to the factory Buffalo Bore ammunition. In order to minimize variables, a commercially available bullet (the Sierra 400gr. flat nose) was selected first, and Winchester 296 powder. With Jack’s suggested starting points, velocities were checked over a range of charge weights. 296 responds very well, in my experience, when there is a heavy enough bullet in front of it. Only the very top end loads came out of the gun without soot on the cases (suggesting that pressure was finally high enough to seal the chamber). Anecdotally, I have heard that some of the ammo companies have tried much heavier loads with 296 with no problems. However, recoil must have been severe, and I personally have no need for any more. Thus, the intrepid reloader who wishes to exceed this data is on his own.
Another check on the data was performed by using the Quickload program. Although the data model for Quickload cannot be perfect, and indeed the author warns that it may be off for straight-walled cartridges, it turned out to match the data very well. Just be sure to put the EXACT case capacity, as well as bullet dimensions and OAL, into the program. Quickload cannot account for all variations in all lots of all components, but my experience is that it will get you in the ballpark much faster, and much more safely, than guessing. Like 296 powder, the data model for Quickload seems to work better in straight-walled cartridges when a fairly heavy for caliber bullet is used.
After the loads with 296 were found to perform well and in a predictable manner, it was desired to test a surplus powder, WC820, from www.gibrass.com. This is definitely getting off the beaten track as far as handloading is concerned. For one thing, there is no published data. For another, non-cannister lots of powder can vary considerably. The reloader with WC820 is advised to test it in other cartridges first, where the performance of that exact lot can be compared to other known powders. Burn rates for WC820 have been reported as fast as AA#9, and as slow as H110. Accordingly, it should be treated as having the fastest possible burn rate and by working up slowly. That is exactly what I did, comparing my lot of WC820 to the performance of WW296 in the .45 Colt, before tackling the JRH.
As it turned out, my lot of WC820 seems to have a burn rate similar to VV N110, which is faster than 296. The data shows that less powder is needed to reach the same velocity levels, indicating that pressures are likely higher. WC820 performed well in this cartridge and has a bit less muzzle blast than 296, although that is a subjective judgment.
With some data at hand for the 400gr. Sierra, it was time to try cast bullets. The Beartooth 440gr. bullet was up next. That bullet was designed (by yours truly) to duplicate the weight of the factory 440gr. Buffalo Bore loading, but seated slightly deeper in the case. The shorter nose would allow the bullet to be used in Freedom Arms guns with their slightly shorter cylinders, and also allow for more bullet jump under heavy recoil. The loss of case capacity is insignificant as far as maximum performance, but load data should be adjusted if other 440gr. bullets are used.
Bullets, left to right are: 300gr. Hornady FTX; 300gr. Hornady FTX with tip removed; 350gr. Hornady XTP-HP; 350gr. Sierra JHP; 350gr. plated (manufacturer unknown); 400gr. Sierra FP; Beartooth 440gr. hard cast; and 500gr. Hornady FP.
A cartridge like the .500 JRH gets a little weary to shoot all day at maximum loads, so some lighter loads were worked up with various powders. Arbitrary performance levels were chosen for medium and fast powders to match the type of shooting desired. The lightest loads with 350 grain bullets (type unknown, but plated) are indeed quite pleasant to shoot.
High velocities can be obtained with 350gr. bullets and 296, but like smaller cartridges, light bullets with 296 yield impressive muzzle blast. 300gr. bullets can be driven to impressive velocities for those who wish – how does nearly 1,600fps fro m 6.5” barrel sound?!?!?!? Bullets were chosen on the basis of availability, and powders were for the most part what was on hand. Hopefully, this is a broad enough sample for the experienced handloader to use in guiding their own choices.
The careful handloader will note the differences between maximum charges with WC820 and WW 296 with different brands of 350 gr. bullets. Note in particular that the 350gr. Sierra HP is seated longer than the 350gr. Hornady XTP, and uses about 0.050” less powder space. Powder charges should be adjusted accordingly.
500 grain bullets can be used in the JRH, but not without issues. In my gun, case necks must be reamed to accept 500 grain bullets, which defeats some of the convenience of the JRH. My personal feeling is that 440gr. bullets are a reasonable top end, but for those reloaders who must scratch the itch, it is possible.
9 grains of Titegroup works well as a mild load with several different bullet weights. The .500 JRH is very controllable with this load.
14 grains of Accurate Arms #5 is an excellent load with several bullet weights. It is entirely adequate for the largest game (note it is very close to the same velocities as the Buffalo Bore factory 440gr. / 950fps load which will go through a bison).
17-18gr. of Blue Dot is a modest step up, but a surprising amount of unburnt powder was encountered with 350gr. bullets. I don’t have enough experience with Blue Dot to say whether this is normal or not.
WC820, for those who have it, is a useful step down from 296. The muzzle blast was noticeably less, while velocities were close.
Full power loads end up being a case full of WW296, or close. While every lot of powder can be slightly different, it appears that WW296 is ideal for maximum performance, and also, maximum muzzle blast! The muzzle blast can literally clear the shooting bench.
Personal opinion, but 300gr. bullets don’t do much for me except as light practice loads. My Ruger Bisley .45 Colt revolvers can handle that weight with aplomb. Still, it remains tempting to find out what a Hornady FTX (without the tip) will do to a varmit at close to 1,600fps. These bullets were purchased mistakenly, but with components in short supply, it was an easy decision to pull the tips out and see what they would do. Other 300gr. bullets should yield similar performance. With optical sights and a fairly flat trajectory for a handgun, they may be an interesting long range deer load. Please note that these were worked up with a second lot of WW296 due to running out of the original lot.
350gr. bullets are very controllable at the lower velocities (900-1,100fps) and a reasonable choice for practice, as well as deer and pigs.
400 and 440gr. bullets are where this cartridge shines, again, personal opinion. Either bullet at 1,000 – 1,100fps will go through the largest game, yet be more pleasant to shoot than 300 or 350gr. bullets with maximum loads. Shaving 200-300fps off of the top loads makes a world of difference in ease of handling the recoil. Like the .45 Colt, in the .500JRH I’ve slowly gravitated toward a reasonably heavy bullet at around 1,000fps.
500gr. Hornady FP bullets required neck reaming, as noted above. The recoil was not substantially worse than the 440gr. bullets at 1,300fps although point of impact is noticably higher. Only three rounds were tried; my can of WW296 had almost exactly 80 grains of powder left and this was the last load fro m it.
Any time standard off-the-shelf dies are not available for a cartridge, modifications to existing equipment can solve the handloader's problems. As noted in Part I, the only modification required to .500 S&W dies was removing 0.2" off of the bottom of the seating/crimp die. Although this was done in a lathe with carbide tooling for the RCBS seater/crimp die, a lathe is not required. To demonstrate, when a Redding Profile Crimp die was found to require the same modification, a common bench grinder was used with no problems. The body of the die was stuffed with damp paper towels and slowly rotated to keep the material removal equal. The good folks at Redding may cringe at this modification, but it shows how this can be done with simple workshop tools. Just be sure to clean all of the grit out of the die body. The "workshop" in this instance is the tailgate of my pickup truck. Please note that Redding does offer custom die modifications.
The die body has been shortened enough, note the damp paper towel stuffed in it to help keep the grit out.
For ease of use, a slight chamfer was put on the inside of the die and it was cleaned up in the lathe. However, it was tested and worked perfectly well, straight from the grinder (once it cooled down and was hosed out with WD-40). Note, a six-jaw scroll chuck is a wonderful thing for work of this nature.
Other suggested modifications:
Note the two seater stems at the top left. The far left is fro m a .44 magnum die set, before a lathe was available. Sometimes bullets with very wide flat noses don't fit bullet seating stems. This one had the lip ground off, leaving only the flat center, and works very well with a variety of bullets. This shows a lathe is not required to make this modification and in fact works so well I never got around to cleaning it up on the lathe. The second seating stem from the left is for the .500 S&W die set and was turned flat in the lathe.
The die body and expander on the right side of the die box are fro m the .500 S&W die set. It probably works just great, but I've never used it. My preference for neck expanding has long been to use the Lyman "M" die, or my own copies. Lyman currently lists one for the .500 S&W; being in a hurry I turned the expander in the lower right corner of the picture and mated it up with other "M" parts, the die body and adjustment stem immediately above it.
Trimming cases should not be a problem for any lathe-type case trimmer that can handle the .500 S&W. For a variety of reasons, I have moved to the Lee system for case trimming. A large sized cutter (body diameter approximately 0.555") is required, as well as a custom length pilot. While Lee can make custom parts, in the interest of time, I took a pilot for the .500 S&W and cut it in two and then soldered the pieces back together so cases could be trimmed to 1.4." The shellholder is the same as the .500 S&W (#16) and the base is identical for all cases in the Lee system, as far as I am aware. Those parts are in the lower left corner of the picture.
My RCBS/Wilson chamfering tool worked just fine even though it is marked "17 - 45." The tool will handle inside chamfers up to around 0.6" although the outside chamfer is just barely large enough for the .500 brass.
Cases can be formed fro m .500 S&W brass by several methods, if required. Any of the lathe-type trimmers should work. One of the reasons I favor the Lee system is the speed that can be obtained using a drill press:
Of course if you do have a lathe, it is probably the very best way to trim or modify cases. And if you don't have a six-jaw scroll chuck, stop what you are doing right now and go and order one (and a backing plate). They are marvelous for handling thin tubing or any other workpiece that could be damaged by the chuck jaws. And, the grooves in the jaws act as a positive stop for the case rim, which helps in maintaining consistent dimensions. Here, case necks are being reamed by a slightly undersized 1/2" drill bit, with a depth mark on the drill bit. Reaming case necks was only required for testing 500 grain bullets, and not required for any other bullet weight.
The die box is getting full! Fortunately, the RCBS die boxes have lots of room for the extra dies and whatnot. Crimping will be covered in Part III.
As noted in Part I and Part II, modification to the seater/crimp die is required to use .500 S&W dies for the .500 JRH. And crimping is very important to the .500 JRH! The relatively light gun weight and high performance levels (read: recoil) available with this cartridge make the possibility of bullets jumping the crimp all too real. While the RCBS seater / crimp die worked fine with jacketed bullets, cast bullets have less friction with the case mouth and are more likely to jump crimp.
Two possible resolutions came to mind: the Redding profile crimp die, and also, the Lee "Factory Crimp" system with the stab-type crimp (note: NOT the "carbide" factory crimp die). Both will be tried to gage their effectiveness vs. the
The RCBS seater / crimp die is on the left; the Redding Profile Crimp die next to it, and the various parts on the right bear some explaining. Since Lee does not catalog a factory crimp die for either the .500 S&W or .500 JRH, one was put together out of various parts. A Lee Factory Crimp die in .458 Win Mag was surplus to my needs, so the die body was cut down short enough for the .500 JRH. This left the die body so short that it had to be screwed into the press from the bottom, which was acceptable for experimenting. Later it was discovered that die bodies for shorter bottlenecked cartridges like the .44-40 could be used.
Next, a collet was needed. Various collets from other Lee Factory Crimp die sets were measured. The material that Lee uses for the collets was unknown, so an old steel bolt of unknown compsition was carefully selected (read: grabbed the first thing in the scrap pile that was big enough) and with some guessing on the dimensions, a collet was made. The slits in the collet aren't very straight, but that doesn't seem to hurt anything. The "mystery metal" is holding up well enough (some moly wheel bearing grease was applied to prevent galling).
From left to right - RCBS, Redding, and homemade Lee FCD.
Testing at the range, with 15 test rounds using the 440gr. Beartooth bullet and 28.5gr. of WW296, showed which die made the best crimp. The results were a little surprising in that the Redding Profile Crimp die was not substantially better than the RCBS seater/crimp die for the .500 S&W. The process was to load 5 rounds which had all been crimped with the same die, shoot 4 of them, and remove the 5th for measurement.
The bullet crimped with the RCBS die showed about 0.030" of jump. Average for 4 shots was 1,300fps.
The bullet crimped with the Redding Profile Crimp die showed about 0.025" of jump. Average for 4 shots was 1,304fps.
The bullet crimped with the home-brewed Lee Factory Crimp die showed about 0.007" of jump. Average for 4 shots was 1,334fps.
None of the rounds jumped the crimp anywhere near enough to tie up the cylinder, but it is interesting that the cases which had been crimped with the homemade FCD came out of the gun substantially cleaner than cases crimped with the other two. Average velocities with the FCD crimped cases were about 30fps more than the other two, although 4 rounds is not a very large sample. It is also reasonable to say that different adjustments to the crimp die could have changed the results somewhat. However, the Lee system seems to be the best for getting the very tightest grip on the bullet. Note, also, that jacketed rounds can be crimped with satisfaction with any of the three dies, as jacketed bullets have a great deal more friction with the case mouth.
The .500 JRH appears to be one of the best options for the serious big-bore handgunner who wants to carry a standard sized revolver that can be reasonably controllable with one hand and no porting. Brass is easy to form, loaded ammo is available, and components are plentiful. The Magnum Research gun is an outstanding value and can be loaded fro m mild to wild.
Special thanks go to:
- JWP475, a.k.a. John Parker, who introduced me to Jack Huntington and started me on this journey.
- Whitworth, a.k.a. Marko, for his encouragement and suggestions.
- J. Marshall Stanton of Beartooth Bullets, who kindly added my bullet design to his inventory.
- Mike Rintoul of Grizzly Cartridge, who talked shop about .500 handgun cartridges, hunting, and mutual friends at the NRA convention in Houston.
- A forum member who sent me cases for another competing .500 cartridge for comparison, and who wishes to remain anonymous.
- And last - to Jack Huntington, for taking me under his wing and trusting me to use his new creation in the field (not to mention backing me up with one of his double rifles). Thanks Jack!