The Cartridge’s Genesis
.40 S&W Origins
The .40 Smith & Wesson (.40 S&W) emerged from a period of critical evaluation within law enforcement. Following incidents involving a perceived lack of stopping power with the 9mm, the law enforcement community sought a cartridge that could deliver a greater impact. Born from a collaboration between Smith & Wesson and Winchester, the .40 S&W entered the scene with a clear mission: to replicate the ballistic performance of the 10mm Auto in a shorter, more manageable package, that would fit in existing 9mm-sized frames. It achieved this by “necking down” the case of the .40 S&W to accept a .40-inch (10 mm) diameter bullet. Its introduction in the early nineties was met with great enthusiasm, becoming a popular choice for law enforcement agencies across the nation.
10mm Auto History
The ten-millimeter (10mm) Auto, on the other hand, has a more storied, somewhat turbulent history. Conceived by firearms designer, Jeff Cooper, and introduced by the Dornaus & Dixon Enterprises, the 10mm was designed to be a powerful, full-power cartridge, with ambitions of replacing the .45 ACP. The 10mm was initially embraced, but challenges with its large size, recoil, and ultimately the gun it was chambered in, led to a period of diminished popularity. Initially chambered in the Bren Ten, a gun that was found to be difficult to mass produce.
The Path to Success
The .40 S&W was seen to have a quicker path to success. It filled a niche at a time when there was a huge push to equip law enforcement. Over time, the .40 S&W began to dominate law enforcement due to the fact that the cartridge could be chambered in 9mm size gun frames.
Unpacking the Designs
.40 S&W Design
The .40 S&W is designed to fit in existing 9mm frames. It’s a cartridge that prioritizes manageability. The .40 S&W is constructed with a straight-walled design. The bullet diameters are, typically, .400 inches. The case length is around 22 millimeters, and its overall length is generally kept to dimensions that allow it to function within the existing frames. This design allows for a robust performance in a more compact, easily wielded form factor.
10mm Auto Design
The Ten Millimeter Auto (10mm) Auto, in contrast, prioritizes ballistic performance above all else. The cartridge is known for its longer case length, which can be around 25 millimeters, which allows for greater powder capacity and the ability to launch heavier bullets at faster speeds. The standard bullet diameter is the same at .400 inches. The 10mm’s design gives it a significant advantage in raw power and muzzle energy.
Recoil Characteristics
The Ten Millimeter Auto’s full-power nature and the size of the cartridge, contribute to more substantial recoil when compared to the .40 S&W.
A Ballistic Ballet: Velocity and Energy
Velocity Advantages of the 10mm
The heart of any cartridge comparison lies in its ballistic performance, how it performs in flight. In this area, the ten-millimeter Auto often holds a clear advantage. It all comes down to the physics of launching projectiles.
10mm Auto Powder Capacity
The 10mm, with its larger case and increased powder capacity, is generally capable of achieving higher velocities, especially with heavier bullet weights. The heavier the bullet and the faster it’s traveling, the more kinetic energy it carries. Think of it this way, a larger payload moving at a high rate of speed. Depending on the bullet weight, the 10mm can often generate significantly more muzzle energy than the .40 S&W.
.40 S&W Ballistics
The .40 S&W still provides sufficient performance. Its typical bullet weights range from 155 to 200 grains. While the velocities are generally lower than the 10mm with similar bullet weights.
Trajectory Comparison
The trajectory, the path the bullet takes, is also critical. Both cartridges, due to their relatively flat trajectories within typical handgun ranges, are generally manageable in terms of aiming. However, the increased velocity of the 10mm often results in a slightly flatter trajectory, which might translate to a marginal advantage at longer ranges.
Stopping Power and On-Target Impact
Factors Affecting Stopping Power
When talking about stopping power, the ability to neutralize a threat, the story becomes more complex than just raw energy numbers. While a higher muzzle energy gives the 10mm Auto a statistical edge, stopping power is influenced by a range of factors.
- Bullet design: Expansion of the bullet after it hits the target.
- Penetration: How deep the bullet goes into the target.
- Wound channel: The size and shape of the hole the bullet creates.
- The target’s response: It’s ability to move after being hit.
.40 S&W Terminal Ballistics
The .40 S&W, with its good balance of power and controllability, has always demonstrated good stopping power. Its terminal ballistics, what happens when the bullet strikes a target, are often considered effective in a wide range of defensive situations.
10mm Auto Terminal Ballistics
The 10mm’s heavier bullets and higher energies translate into impressive terminal ballistics. The larger wound channels and increased penetration often equate to greater stopping potential. It’s considered by many to be the most powerful handgun cartridge available in a semi-automatic handgun.
Available Handguns: A Look at Platforms
.40 S&W Firearms
The choice of firearms available for each cartridge is a key consideration.
The .40 S&W found a wide range of handguns, including those from Glock, Smith & Wesson, and SIG Sauer. This is important because it provides more options to the shooter, allowing them to find the best platform for their hand.
10mm Auto Firearms
The ten-millimeter, while once more limited, is seeing a resurgence in popularity. There are options from Glock, Colt, and Springfield Armory. The selection has grown.
Ammo Availability and Cost
.40 S&W Ammo Availability
The price and availability of ammunition are crucial considerations for any shooter.
The .40 S&W, due to its widespread popularity, enjoys a wide selection of ammunition from multiple manufacturers. The availability is generally good. The cost of .40 S&W ammunition is generally competitive. It’s usually less expensive than 10mm ammo.
10mm Auto Ammo Considerations
The ten-millimeter, though not as widely available as the .40 S&W, is seeing increased demand which has led to better availability and the growth of various ammunition types, including training rounds and hunting loads. Ammo costs tend to be higher than .40 S&W due to the cost of components.
Purpose and Intended Uses
.40 S&W Applications
The .40 S&W has become a stalwart of concealed carry. It offers a good balance of power and recoil, making it suitable for defensive purposes. It is also favored by some law enforcement agencies and for home defense.
10mm Auto Applications
The ten-millimeter’s power, its suitability for hunting medium-sized game or outdoor protection. The ten-millimeter’s longer range and increased stopping power make it an ideal cartridge for protection in the wilderness or situations where more power may be required. It can also be used for self-defense.
Weighing the Pros and Cons
.40 S&W Advantages
The .40 S&W provides an excellent balance of performance and manageability. Its lower recoil makes it easier to handle, particularly for new shooters. The wide selection of firearms and ammunition, combined with its lower cost, make it an accessible choice. It’s perfect for self-defense and concealed carry. The main disadvantage is that it lacks the power of the ten-millimeter.
.40 S&W Disadvantages
The .40 S&W, with its good balance of power and controllability, has always demonstrated good stopping power. Its terminal ballistics, what happens when the bullet strikes a target, are often considered effective in a wide range of defensive situations.
10mm Auto Advantages
The ten-millimeter is unmatched in terms of its power. The higher muzzle energy and ballistics give it more range and stopping potential. Its the ideal choice for hunting.
10mm Auto Disadvantages
The downside is that the recoil can be more challenging. The ammunition and firearms are also more expensive.
Final Thoughts
The .40 Smith & Wesson and the ten-millimeter Auto are both superb handgun cartridges. The .40 S&W is the right choice if you want an easy-to-handle option that has good accuracy, reliability and availability. The ten-millimeter Auto is the right choice when maximum power is a must and you’re prepared to manage increased recoil and pay more for ammunition. Both these cartridges offer excellent performance depending on your specific requirements. The “best” choice is not a fixed answer, but a personal one.
Ultimately, choosing between these cartridges involves considering your personal needs, shooting experience, and intended use. Take time to research your needs and wants so that you can make an informed decision.
Frequently Asked Questions
Which cartridge is better for beginners?
For beginners, the .40 S&W is usually recommended due to its lower recoil and broader availability of firearms.
Is the ten-millimeter suitable for concealed carry?
While possible, the ten-millimeter’s recoil can make follow-up shots more difficult in stressful situations.
How do the recoil of these cartridges compare?
The ten-millimeter has significantly more recoil than the .40 S&W.
Can you convert a .40 S&W gun to ten-millimeter?
In most cases, you cannot do a straight conversion. You’ll need a different barrel, and in some cases, a new slide. The .40 S&W frame is sized for this cartridge, and in most cases, it’s smaller than the ten-millimeter.
