September 29, 2015
By Brad Miller, Ph.D.
Johnny Rowland introduced a new pistol cartridge in 2014, the 960 Rowland. It is a high-powered 9mm caliber cartridge and is offered with a conversion barrel for a Glock Model 19, a 9mm Luger caliber pistol. A conversion barrel comes in two versions. One is threaded and includes a compensator, the other is extended with ports. Rowland claims the 960 produces .357 Magnum performance from the Glock 19.
The 960 uses a tapered, rimless 23mm long brass, whereas the 9mm Luger's brass is 19mm long. The 960 and 9mm Luger have the same maximum cartridge overall length, so the bullet has the appearance of being seated very deep in the 960 case. The 960's longer case prevents its use in a 9mm Luger chamber.
Factory 960 ammunition is loaded in Starline 9X23 Comp brass, and is what I used for developing these handloads. The 9X23 Comp is Starline's version of the 9X23 Winchester, a very high-powered 9mm cartridge. However, the 960 Rowland has a shorter overall length than the 9X23 Winchester. The 960 will fit in a 9mm length gun, such as the Glock 19, but the 9X23 Winchester is longer, like a .38 Super, 10mm or .45 ACP, and requires a gun frame that will accommodate the longer round, such as a 1911-type pistol, or in Glock terms, a G20/21/29/30/36/40/41 sized gun.
The 960 is essentially a longer 9mm Luger case and can be loaded with regular 9mm Luger dies, though Hornady makes a 9X23 die set distinct from their 9mm Luger dies. I used a Dillon 9mm Luger size die, but belled, seated and crimped with .38 Super dies since it has the same case length as the 960. I also load .38 Super, so I was already setup for that length of case and didn't want to change my 9mm dies back and forth between the 960 and 9mm Luger.
Rowland is the only company that currently offers loaded ammunition for the 960, and there is no published load data. However, there are benchmarks for performance, and the kind folks at Rowland provided some load information and pressure guidelines, for which I gratefully thank them.
Factory ammunition performance for the 960 in a 4.25-inch barrel runs a 115-grain bullet around 1435 feet per second (fps), a 124 grain bullet around 1246 fps, and a 147 grain bullet around 1050 fps.* My sample of factory ammunition clocked the 115-grain load at 1361 fps and the 147 grain load at 1031 fps from a 4.16" barrel. The 124-grain round was not available at the time of my tests.
The 960 Rowland does not yet have a SAAMI pressure rating but Rowland says cartridge pressures are in the 40,000-45,000 psi range. Rowland's current load for a 115 grain Hornady XTP bullet is 8.1 grains of Alliant Power Pistol seated to 1.160 inches.* QuickLOAD internal ballistics software version 126.96.36.199 estimated its pressure at 47,939 psi. This pressure is higher than the limit set for 9mm Luger +P (38,500 psi), but is below that of the 9X23 Winchester (55,000 psi).
QuickLOAD software (QL) was used to guide load development based on its estimated pressures. QL estimates pressure based on the volume of the case, bullet weight, length, material (friction?), seating depth and the burning properties of the gunpowder. QL makes educated guesses. But it is still guessing, and is not the same as rigorous lab testing with a piezoelectric transducer under controlled conditions. The author/s of QL is/are fully aware of this and the software comes with many warnings and disclaimers with these facts in mind.
I found QL especially useful for estimating pressure changes associated with bullet length and overall length. Short bullets reduce pressure because they don't take up as much space in the case when they are loaded to the same overall length as longer bullets of the same weight. Less pressure also means less velocity with the same amount of gunpowder. However, according to QL's calculations, increasing the charge weight with the short bullets suggests that they can achieve higher velocity than the long bullets when they are loaded to the same pressure. This was tested, and assuming that the relative pressure estimations were maintained, QL's prediction was supported: the shorter bullets were ultimately faster.
Fired cases were inspected and measured for maximum expansion at the head where the case is not supported by the chamber. My 960 Rowland barrel does not provide full case support up to the extractor groove, and this unsupported region is where brass fails from excess pressure.
Measurements from brass of factory ammunition and ammunition loaded with the factory data was used as a guide for how much expansion might be expected for "typical" ammunition for this cartridge. The criteria for an excess load was excess case bulge into the unsupported region of the chamber. Excess bulging here is visible as an imprint of the feed ramp. Excessive bulging indicates the pressure has exceeded the practical limit of what the brass might contain in the unsupported region. Fired cases that showed a feed ramp imprint made a line about 0.235 inches up from the base (black arrow in the figure). None of the load data presented in this article produced excessive case expansion in my barrel.
Long case, short cartridge / Bullet Nose Shape
The long 9x23 case means that some traditional 9mm bullets are not an ideal fit. The nose of many 9mm bullets is too long for this cartridge and result in the bullet's shoulder positioned below the case mouth. When a regular crimp is applied to these bullets, there is a gap between the case mouth and the bullet. The Hornady 124-grain XTP bullet is an example. It has a long, narrow tipped conical nose, and when seated, the case mouth edge is exposed.
The consequence of the exposed case mouth is that it scrapes the chamber roof during feeding while the cartridge is still at a steep angle. This produces more friction that you can feel, and I experienced some feeding stoppages at that point with these types of bullets. One can apply a more aggressive crimp to eliminate the gap and give the case mouth a rounded profile. However, this cartridge headspaces on the case mouth, so you don't want to get too aggressive.
Bullets with a short, wide nose are a better fit for this cartridge. They eliminate the exposed case mouth, provide a more moderate feeding angle and smoother feeding. The Nosler JHP bullet is an example of a short, round nose and fits the 960 perfectly. Sierra and Remington JHP and .357 SIG-style bullets also have ideal nose shapes, and I experienced no feeding problems with these bullets.
Hornady's 115 and 124-grain 9mm XTP bullets (and their sister HAP bullets) have long, narrow noses, but the 147 grain XTP has a wider tip and fed well. In fact, Hornady's .357 caliber XTP revolver bullets have a more favorable nose profile for the 960 than their 9mm XTP bullets, because they have a shorter, wider nose, and they fed very well in the 960.
While .357 caliber bullets might seem oversized for the 9mm caliber, some folks use them in their 9mms. Many 9mm bores are larger than 0.355 inches. In fact, both the 960 Rowland barrel and the Glock's original 19C barrel slugged at 0.357 inches, making oversize bullets an ideal fit, and 0.357-inch jacketed and 0.358-inch lead bullets were included in load development. Not all 9mm-sized chambers will accept a 0.357-inch or larger bullet, since this also expands the brass more than a 0.355-inch bullet, but this barrel's chamber accepted the larger bullets with no problems.
Bullet length affects pressure and is another reason why bullets with a short, wide nose, are desirable, because, all else being equal, short nose bullets are shorter than long nose bullets. Short bullets help to keep pressure low, and as noted previously, you might get more velocity from them for the same pressure.
Several different bullet designs were tested, but preference was given to bullets that are short for their weight in order to maximize velocity. For example, Sierra FMJ RN bullets were used because they are some of the shortest available for that design. For comparison, a Hornady 115 grain FMJ RN bullet measures 0.551 inches, while the Sierra bullet measures 0.535 inches. QL estimates the shorter Sierra bullet produces 4,808 psi less pressure when they are loaded to the same length of 1.165 inches over 10.0 grains of Accurate No. 7. That's a big difference in pressure due simply to bullet length.
The noses of the SNS Casting 125 and 158-grain .38/.357 caliber round nose flat point bullets are especially short for their weight, and they were selected for that reason. In fact, the 125 grain bullet is shorter than many 115-grain bullets, and the 158-grain bullet is shorter than many 147-grain bullets. This permits maximizing their potential velocity.
The Starline 9x23 Comp brass will handle any bullets that the 9mm Luger will, including up to 158/160 grains. The long, heavy bullets, however, can bulge the case a little because they are pushed so deep, and if the bulge is big enough, they might not fit in all chambers. The Sierra 170-grain FMJ bullet sometimes used in the 38 Super is too long and bulged the case too much to fit in my chamber.
The SAAMI maximum overall length of the 9mm Luger cartridge is 1.169 inches, and this is likely the maximum length for the 960 as well, since it is intended for a 9mm-length firearm. Magazines should accommodate ammunition with round nose bullets loaded to that length. However, flat nose bullets loaded to that length might not fit in the magazine because they have a longer diagonal length and often need to be seated deeper.
My Glock factory magazines function perfectly with round nose bullets seated to 1.169 inches, though I loaded them to 1.165 inches to account for variation in overall length than can occur during loading. Rowland** recommended that Hornady JHP bullets be seated to 1.160 inches. Flat nose bullets at that length were too long to fit freely in my magazines without sticking, however, so I seated them to 1.150 inches, and even the widest flat nose bullets fit with no issues at that length.
Overall length affects pressure, and the deeper the bullet is seated, the greater the pressure, so you'll want to load them as long as is practical. Recall that the estimated pressure of the factory 115-grain load seated at 1.160 inches produces 47,939 psi pressure. Seating it to 1.150 inches raises the estimated pressure to 50,483 psi. I tried this load at 1.150 inches and did not see signs of excess case bulge in my barrel.
Pay close attention to overall length, and try to minimize variance. It's also why you want good neck tension for your bullets to prevent setback as this will raise pressure, and if you're working with new brass, sizing them is a good idea to increase neck tension.
Medium-to slow-burn rate pistol powders are best suited to provide the highest velocities at acceptable pressures in the .960. Case capacity limits which powders are practical. Most of the powders listed required some degree of compression with full powered loads.
Flake powders Power Pistol and BE-86 compressed easily with no obvious increase in pressure required to seat the bullet. However, dense powders don't compress as readily, and if they occupy too much space might require super-compression. Super-compressed powder has some 'spring' to it, and the bullet does not stay at its seated overall length. The seating die has to be adjusted deeper so the eventual overall length is appropriate after bullet spring-back. VihtaVuori N105 was super-compressed and, in some instances, the pressure required to seat lead bullets to the desired overall length deformed the bullet's nose.
Alliant BE-86 (not to be confused with Bullseye) was not in the QL database, because it was only recently introduced, so there are no estimated pressures for this powder. Its load data is based solely on case expansion.
Powders other than those used for this article can work in the 960. Be sure to watch carefully for excess pressure signs during your load development.
These loads were developed with standard Winchester small pistol primers (WSP), the same primers used in the factory ammunition. Primer flow was apparent, but might be expected at these pressures. Also, some degree of primer flow is common in Glock pistols, in my experience. Some Winchester rifle primers were used during load development, and some misfires occurred in the Glock. Rifle primers have thicker cups and are less sensitive, which can produce ignition problems in some pistols.
Handloaders can also use Winchester 9x23 brass. It is stronger in the unsupported region than the Starline brass because its walls are thicker and reduces the likelihood of excessive case bulge.
This also means that the Winchester brass has less capacity than the Starline, so less powder is required for the same velocity. The Winchester brass required 5 percent less Accurate No. 7 to drive a 125-grain Hornady .357 XTP bullet to the same velocity as the Starline brass. The Winchester brass' reduced capacity also means it will produce more pressure, which will usually show up in the primers. This might produce excess primer flow in some pistol primers.
The Winchester's thicker walls have a downside, however. The walls are thick high up the case, and even some 124-grain bullets bulge the case because they are seated so much deeper than they would be compared to their depth in normal 9x23 Winchester ammunition. As a result, the 124-grain Nosler JHP bulged the Winchester case so much that it would not fit in the chamber.
Pulled bullets showed that some were reshaped to boat tail bullets when seated in the Winchester brass, the base being visibly and measurably compressed. Whether some bullets would fit in the chamber depended on how amenable their base was to distortion. For example, the base of the Remington 147-grain FMJ bullet was compressed, but it still would not fit in the chamber when fully seated, whereas the Eggleston 148-grain cast bullet did fit. The boat tail Hornady 147-grain XTP fit the chamber, but it was also distorted; the boat tail contour was extended farther up the bullet.
A boat tail is not a problem, since the Hornady bullets come that way. Whether forming the boat tail by seating the bullet in the Winchester brass causes concerns is not known.
The test gun was a Glock 19C with a 4.16-inch Rowland 960 barrel. Velocity was recorded with a Shooting Chrony chronograph at about ten feet.
Load data in the tables are the maximum charge weights but proved safe in my barrel. The highest estimated pressure calculated in QL was 50,483 psi from the Rowland load data of 8.1 grains of Power Pistol and a 115-grain XTP bullet, though seated to 1.150 inches. All other estimated pressures were below this, and are listed in the tables.
I report the estimated pressures, but I do not claim or imply that they are accurate. I only report them to show what the QL software calculated. I used the estimated pressures as a guide for load development, and I limited the loads to estimated pressures that did not exceed that of the deeper seated factory load, but the most important criteria was case expansion.
Starting loads should be reduced by 15 percent. Work up gradually and watch closely for pressure signs to determine what is safe in your barrel.
I found loads that would equal the factory velocity with 115-grain bullets, and the 124 and 147-grain loads were faster than the factory specifications by roughly 100 fps. Even the 158-grain cast bullets equaled or exceeded the factory 147-grain velocity.
Several powders produced high performance with varying bullets. Accurate No. 7 produced some of the highest velocities with many bullets. Power Pistol produced some of the widest extreme spreads in velocity, though not consistently. Silhouette tended to produce excess bulging at less velocities than the other powders.
The loads listed in the tables were safe in my barrel, but this does not mean they will be safe in your barrel. Many factors related to the barrel and ammunition will determine chamber pressure and brass expansion. The amount of case support is absolutely critical, and you must watch closely for excess case expansion here as it might be one of the first indicators that your load is overpressure for your barrel. For example, ammo that did not show a feed ramp imprint in the Rowland barrel, did show a feed ramp imprint when fired in a Nowlin 9x23 barrel that had less case support. The brass is thinner higher up the wall, and stretches more with the same pressure. Thus, loads in the Starline brass that were deemed safe in the Rowland barrel were not safe in the Nowlin barrel.
Chambers are different, and different barrels show different pressure signs with the same ammunition. The length of the throat can influence pressure. A longer throat will reduce peak pressure, and throat length can vary from one barrel to another. Tighter chambers and bores might produce higher pressures.
Gunpowder varies a little from one lot number to another, and this affects pressure and velocity. Using different primers could produce different pressures, and even the same primers could vary between lots. Brass strength and capacity might also differ between lots and expand more/less with the same loads.
All of these factors will determine how your barrel responds to your loads. That's why it's so important to carefully work up your loads in your gun to determine what it will safely handle. Be very mindful of any changes you make in your loading components.
The 960 is capable of making Major power factor for IPSC competition. Major power factor is calculated as bullet weight times velocity divided by 1000, and ammunition must achieve at least 165 power factor to meet USPSA rules and 160 for IPSC rules in Open Division.
The 960's cartridge overall length puts it in the same category as 9 Major, a 9mm caliber cartridge that fits in 9mm-length pistols. The 960's distinction is the case length. The advantage of a longer case is that it will accept powders that might overfill a 9mm Luger case. This expands the potential powders that could be used. For example, N105 is capable of making Major power factor in a 9mm-length round, but the weight required for lighter bullets can overflow a 9mm-length brass. The longer 23mm case has enough room.
The author and publisher are not responsible for mishaps of any kind which might occur from the use of this data in developing your handloads. It is the user's responsibility to follow safe handloading guidelines in developing safe ammunition. You use this data at your own risk. No responsibility for the use or safety in use of this data is assumed or implied.
A special thanks to "Dave" at 460 Rowland for patiently answering many questions.
* Information kindly provided by Dan McKensie.
** Personal communication via "Dave."