Locating accurate 10mm Auto load data is essential for harnessing the true magnum-level potential of this legendary semi-automatic pistol cartridge.
This comprehensive guide compiles trusted 10mm Auto reloading data to help you safely develop the perfect round for backcountry defense, handgun hunting, or competitive shooting.
Whether you are loading lightweight 135-grain self-defense projectiles or heavy 200-grain hard-cast bullets for bear protection, always cross-reference these published figures before charging your cases.
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10mm Auto Load Data
| Bullet | Bullet Weight | Powder | Published Starting Load | Published Maximum Load | Published Velocity | Barrel Length / Firearm | Source |
| Nosler JHP | 135 gr | Longshot | 8.5 gr | 9.5 gr (34,800 PSI) | 1,300 – 1,420 fps | 5″ / Universal Receiver | Hodgdon |
| Hornady XTP | 155 gr | CFE Pistol | 7.4 gr | 8.4 gr (35,900 PSI) | 1,150 – 1,280 fps | 5″ / Universal Receiver | Hodgdon |
| Sierra JHC | 180 gr | Blue Dot | 8.5 gr | 10.4 gr | 1,100 – 1,250 fps | 5″ / Universal Receiver | Alliant Powder |
| Hornady XTP | 180 gr | Accurate No. 9 | 13.5 gr | 15.0 gr | 1,150 – 1,280 fps | 5″ / Universal Receiver | Western Powders |
| Cast LFN | 200 gr | Longshot | 7.0 gr | 8.2 gr (35,000 PSI) | 1,050 – 1,170 fps | 5″ / Universal Receiver | Hodgdon |
10mm Auto Reloading Data
| Bullet | Bullet Weight | Powder | Published Starting Load | Published Maximum Load | Published Velocity | Barrel Length / Firearm | Source |
| Barnes TAC-XP | 155 gr | Silhouette | 7.8 gr | 8.8 gr | 1,150 – 1,280 fps | 5″ / Universal Receiver | Western Powders |
| Speer GDHP | 165 gr | Power Pistol | 7.5 gr | 8.5 gr | 1,150 – 1,300 fps | 5″ / Universal Receiver | Alliant Powder |
| Hornady HAP | 180 gr | AutoComp | 6.8 gr | 7.5 gr (36,100 PSI) | 1,080 – 1,180 fps | 5″ / Universal Receiver | Hodgdon |
| Hornady XTP | 200 gr | Accurate No. 9 | 12.0 gr | 13.5 gr | 1,080 – 1,200 fps | 5″ / Universal Receiver | Western Powders |
| Cast WFNGC | 220 gr | Accurate No. 9 | 10.5 gr | 11.5 gr | 1,000 – 1,100 fps | 5″ / Universal Receiver | Western Powders |
Understanding the 10mm Auto Reloading Data
Reading 10mm Auto reloading data requires an understanding of its history and high-pressure design. Originally championed by Jeff Cooper for the Bren Ten pistol, it was intended to deliver magnum revolver ballistics in a high-capacity autoloader. The cartridge headspaces on the case mouth, meaning handloaders must exclusively use a taper crimp to secure the bullet without rolling the brass edges inward. Because the 10mm Auto was notoriously “watered down” by the FBI (eventually leading to the .40 S&W), modern factory ammunition is often underpowered. Handloading is the primary way shooters unlock the cartridge’s original, full-power specifications.
10mm Auto Bullet Weight Reloading Data
The 10mm Auto utilizes a standard .400-inch bullet diameter. While it shares this diameter with the .40 S&W, the 10mm case is significantly longer, allowing for much heavier bullets and more powder. Bullet weights typically range from lightweight 135-grain expanding hollow points to heavy 220-grain hard-cast lead projectiles. The 180-grain bullet is the undisputed all-around standard, offering the perfect balance of velocity, kinetic energy, and barrier penetration. For deep penetration on dangerous game, 200-grain and 220-grain wide flat nose (WFN) cast bullets are the preferred choice.
10mm Auto Powder Reloading Data
Powder selection for the 10mm Auto relies on medium-to-slow-burning pistol propellants that can maximize velocity without causing instantaneous pressure spikes. Hodgdon Longshot and Accurate No. 9 are widely considered the absolute gold standards for generating full-power 10mm loads. Other excellent choices include Alliant Blue Dot, Power Pistol, AutoComp, and CFE Pistol. Extremely fast-burning powders (like Titegroup or Bullseye) should generally be avoided for full-power hunting loads, as they peak too quickly to safely drive heavy bullets to magnum velocities.
10mm Auto Bullet and Powder Combinations
Pairing the right bullet with the appropriate powder is critical for achieving your desired ballistic profile. A 180-grain jacketed hollow point (JHP) paired with a heavy charge of Blue Dot or Power Pistol creates a devastating personal defense or medium-game hunting round. For backcountry bear defense, seating a 200-grain hard-cast bullet over a maximum safe charge of Accurate No. 9 or Longshot guarantees the sustained pressure curve necessary to drive the heavy lead projectile deep through thick hide and bone.
10mm Auto Velocity From Published Data
Published velocity figures for the 10mm Auto firmly place it in the same league as the .357 Magnum. Pushing a lightweight 135-grain bullet past 1,400 fps is easily achievable. More importantly, the cartridge can drive a heavily constructed 180-grain bullet well over 1,200 fps. Even when loaded with massive 200-grain projectiles, handloaders can comfortably achieve 1,150 to 1,200 fps out of a standard test barrel, providing a devastating amount of momentum compared to traditional 9mm or .45 ACP loads.
10mm Auto Reloading Data by Barrel Length
Most published load data for the 10mm Auto utilizes a 5-inch laboratory test barrel, perfectly simulating full-size duty pistols like the classic Colt Delta Elite or the standard Glock 20. If you are running a long-slide hunting pistol with a 6-inch barrel (like the Glock 40), you can expect a very useful velocity gain of 50 to 75 fps, maximizing the cartridge’s energy. Conversely, shooting from a 3.8-inch subcompact pistol (like the Glock 29) will result in a noticeable velocity drop and a tremendous muzzle flash as unburnt powder ignites outside the barrel.
10mm Auto Energy and Ballistics
The 10mm Auto generates outstanding kinetic energy, frequently exceeding 600 to 700 foot-pounds at the muzzle when loaded to its full potential. The high velocity produces a remarkably flat trajectory for a handgun cartridge, allowing skilled shooters to make ethical shots on medium game out to 50 yards and ring steel reliably at 100 yards. The high sectional density of the heavier .400-caliber bullets ensures they retain energy and penetrate deeply at these extended handgun ranges.
10mm Auto Hunting Applications
The 10mm Auto is arguably the most popular semi-automatic handgun hunting cartridge in the world. It is highly favored by backcountry hikers, fishermen, and hunters in Alaska and the Pacific Northwest as a primary defense gun against grizzly and black bears. Loaded with 200-grain or 220-grain hard-cast bullets, it provides the deep, straight-line penetration necessary to stop heavy predators. Loaded with 180-grain expanding hollow points, it is also a fantastic primary hunting round for whitetail deer and feral hogs in dense brush.
Manufacturer Data vs. Independent Testing
Because the 10mm Auto operates at high pressures, relying exclusively on official manufacturer load data is critical. Many early generation 10mm pistols (specifically early Glock 20s) featured partially unsupported chambers. Handloaders chasing boutique, “nuclear” factory ammunition velocities often experience case bulging near the web—famously known as the “Glock smile”—which can lead to catastrophic case blowouts. Always respect published maximum charges and inspect your fired brass for severe bulging, utilizing fully supported aftermarket barrels if you intend to shoot heavy loads frequently.
10mm Auto Pressure and Safety
The SAAMI Maximum Average Pressure (MAP) for the 10mm Auto is a robust 37,500 PSI. Because it is a high-pressure cartridge in a semi-automatic platform, bullet setback is a major safety concern. If inadequate neck tension or a weak taper crimp allows the bullet to be pushed deeper into the case during feeding, chamber pressure will spike to dangerous levels. Crucial Note: While the 10mm Auto historically uses Large Pistol primers, many modern brass manufacturers (like Federal and Blazer) now use Small Pistol primers. Always sort your brass by primer pocket size before loading to avoid detonating a primer in your press.
Best Sources for 10mm Auto Reloading Data
The most reliable sources for load data are the printed manuals and digital databases provided by powder and bullet manufacturers who understand the cartridge’s full-power capabilities. The Hodgdon Reloading Data Center offers extensive digital tables specifically optimized for Longshot, AutoComp, and CFE Pistol. Additionally, the Western Powders data hub is the premier source for Accurate No. 9 recipes, and the Hornady Handbook of Cartridge Reloading provides excellent, pressure-tested data for their popular XTP and HAP projectiles.
Frequently Asked Questions
Where can I find 10mm Auto reloading data?
You can find accurate 10mm Auto reloading data in published manuals from Hornady and Speer, or digitally on the official Hodgdon and Western Powders Reloading Data Center websites.
What powders are listed in published 10mm Auto data?
Commonly listed medium-to-slow-burning pistol powders include Hodgdon Longshot, Accurate No. 9, Alliant Blue Dot, Power Pistol, AutoComp, Silhouette, and CFE Pistol.
What bullet weights are covered in these tables?
These tables specifically cover the optimal .400-inch bullet weights for the cartridge, ranging from lightweight 135-grain self-defense bullets up to massive 220-grain hard-cast lead projectiles.
Does barrel length affect 10mm Auto velocity?
Yes, shooting from a 6-inch long-slide hunting pistol will generally yield a velocity gain of 50 to 75 fps over standard 5-inch test barrel data, while 3.8-inch subcompacts will lose velocity.
Can I use standard rifle primers for 10mm Auto?
No. Historically, the cartridge uses standard Large Pistol primers. However, modern commercial brass is often manufactured with Small Pistol primer pockets, so you must carefully sort your brass and use the corresponding pistol primer.
What is the difference between 10mm Auto load data and reloading data?
There is no practical difference; both terms refer to the precise recipes of powder charges, bullet weights, and primers required to safely assemble the ammunition.
Why do published velocity figures differ between sources?
Velocity figures differ because testing facilities use varying specific test barrels, environmental conditions, brass lot capacities, and primer types during their distinct testing protocols.
Should I use the maximum published load?
You should never start with the maximum published load; always begin with the minimum recommended starting charge and carefully work up while monitoring your brass for pressure signs like flattened primers or case bulging.
Can I use data from one bullet manufacturer for another bullet?
You should only use data specifically designed for the exact bullet profile you are loading, as variations in seating depth drastically alter the internal case capacity and chamber pressure.
Where should I verify 10mm Auto load data before reloading?
You should strictly verify all load data against an official, recently published manufacturer manual or a powder company’s official online database before assembling any ammunition.