Understanding the Glock 20
Chambering and Specs
The Glock 20 holds a distinguished place in the Glock lineup, renowned for its powerful chambering and robust design. This handgun is fundamentally designed to handle the formidable 10mm Auto cartridge. The 10mm Auto is known for its significant power and is often praised for its flat trajectory and stopping power. The ammunition delivers a higher level of energy compared to many other handgun rounds, making it a favorite among hunters, law enforcement professionals, and shooting enthusiasts who appreciate potent firearms.
The Glock 20 is built to withstand the high pressures generated by the 10mm Auto round. This is reflected in its rugged frame, substantial slide, and reinforced internal components. A crucial part of the Glock 20 is its barrel. The barrel is the heart of the firearm’s ability to safely and accurately fire ammunition. It’s precisely manufactured to accept the specific dimensions of the 10mm Auto cartridge.
The internal components, including the slide, the firing pin, the extractor, the ejector, and the magazines are all integral parts that work together to ensure reliable function. Each component plays a critical role in the firing cycle: from feeding the round, to extracting the spent casing, to ejecting it. All are designed and engineered to handle the pressure and the characteristics of the 10mm Auto cartridge.
Understanding the .40 S&W Cartridge
Ballistics and Purpose
The .40 Smith & Wesson (.40 S&W) cartridge, developed jointly by Smith & Wesson and Winchester, emerged as a response to a gap in performance between the 9mm Luger and the .45 ACP rounds. It was designed to offer a balance of power, recoil, and magazine capacity. The .40 S&W quickly gained popularity with law enforcement agencies and civilian shooters alike, becoming a widely adopted cartridge in the handgun market.
The .40 S&W cartridge carries a respectable amount of energy and is known for its effective stopping power, making it suitable for self-defense and law enforcement purposes. Despite the higher energy, the .40 S&W is typically found to have manageable recoil compared to the 10mm Auto, a factor appreciated by many shooters.
Although both cartridges are used for self-defense, there are key differences. The .40 S&W’s dimensions are slightly different from the 10mm Auto. One of the most notable differences is the case length. The .40 S&W has a shorter case than the 10mm Auto. These differences, however seemingly small, have significant implications for ammunition compatibility.
Compatibility: Can It Actually Work?
The Barrel Issue
The most crucial aspect when considering whether a Glock 20 can shoot .40 revolves around the barrel. The barrel is the component that houses the round, and the internal dimensions of the barrel’s chamber must be precisely sized to accommodate the specific cartridge. The barrel of a Glock 20 is designed with a chamber shaped to accept the 10mm Auto round.
Attempting to fire .40 S&W ammunition in a Glock 20 *using the original barrel* poses a number of significant safety hazards. Because the .40 S&W cartridge is slightly shorter than the 10mm Auto, the round may not sit correctly in the chamber. This can lead to a range of problems, from inaccurate shots to potentially catastrophic failures. The headspace, or the distance between the breech face and a point in the chamber, may not be correct.
Furthermore, the extractor and ejector, parts of the firearm’s system designed for the 10mm Auto, might not function effectively with the .40 S&W. The extractor, which grabs the spent cartridge case to pull it from the chamber, might not grip the .40 S&W case securely enough. The ejector, which kicks the spent case out of the pistol, might not function properly.
Magazines also play a part in this compatibility issue. While a .40 S&W round might, with a bit of effort, *seem* to fit into the 10mm magazine, this is not recommended. Using the wrong magazine increases the chance of feeding failures and other malfunctions.
The Risks Involved
Safety Concerns
Attempting to fire .40 S&W ammunition in a Glock 20, without the proper modifications, carries a host of serious safety risks. The most immediate danger is the potential for the firearm to malfunction, potentially leading to injury to the shooter or bystanders.
Misfires: Because the .40 S&W round might not be seated correctly in the chamber, it could fail to fire. This could happen multiple times, creating a dangerous situation for the shooter.
Failures to Extract: The extractor might not effectively grip the shorter .40 S&W cartridge case, leading to failures to extract the spent casing. This can cause a jam, rendering the firearm useless.
Chamber Rupture: If the .40 S&W cartridge doesn’t seat correctly, or if it’s not properly supported, firing it could cause a chamber rupture. A chamber rupture involves the barrel of the firearm bursting, which can cause severe injury.
Damage to the Firearm: Repeated use of .40 S&W in a Glock 20, without a conversion barrel, could eventually damage the firearm. This damage could make the firearm unsafe to use, and could cause the need for costly repairs.
These potential failures, though not inevitable, highlight the critical importance of maintaining proper firearm safety protocols. The potential for injury or damage to the firearm underscores the significance of only using ammunition that is specifically designed for the firearm.
The Safe Solution: Conversion Barrels
Definition and Purpose
While it’s not safe to shoot .40 S&W ammunition in a standard Glock 20, there is a viable solution: conversion barrels. A conversion barrel is a replacement barrel specifically designed to chamber a different cartridge within the same firearm frame. They’re engineered to fit the Glock 20 slide and frame, but with a chamber designed for the .40 S&W cartridge.
The purpose of a conversion barrel is to safely and reliably allow a Glock 20 to fire .40 S&W ammunition. By using a conversion barrel, the shooter essentially transforms the firearm to be chambered for the .40 S&W cartridge, all the while using the same frame. The conversion barrel ensures that the .40 S&W cartridge is properly supported and that the ammunition is fired safely.
Using a conversion barrel generally allows the shooter to continue to use the original slide, frame, and other components of the Glock 20. However, in most cases, when using a conversion barrel to switch to .40 S&W, the shooter should *also* use magazines made for .40 S&W ammunition, and not the original 10mm magazines. Some models may also need the recoil spring assembly changed.
Alternatives to Consider
Shooting the 10mm Auto
It’s important to explore the alternatives to firing .40 S&W ammunition in your Glock 20 without a conversion barrel.
Embrace the 10mm Auto: The 10mm Auto is a powerful and versatile cartridge. If you have a Glock 20, consider using the ammunition it was designed for. The 10mm Auto has a proven track record of reliability. If you appreciate the power of the Glock 20, shooting 10mm Auto is the best way to get the most from the firearm.
Consider Buying a .40 S&W Glock: For those seeking to shoot the .40 S&W cartridge, the easiest and safest solution is to purchase a Glock model specifically chambered for that round. Many Glock models are available in .40 S&W. Examples include the Glock 22 (full-size), Glock 23 (compact), or Glock 27 (subcompact). This ensures that you are using a firearm designed from the ground up for the .40 S&W cartridge.
Conclusion
In conclusion, *can a Glock 20 shoot .40*? The answer, in its simplest form, is *no*, not safely, without the use of a conversion barrel. Attempting to fire .40 S&W ammunition in a Glock 20 using the original barrel poses significant risks, including the potential for misfires, failures to extract, chamber ruptures, damage to the firearm, and ultimately, the potential for serious injury.
The safest and most practical options are to either embrace the 10mm Auto cartridge in your Glock 20, or to acquire a Glock model specifically chambered for .40 S&W if you want to use that particular ammunition. If you want to use .40 S&W ammunition in your Glock 20, you should purchase a conversion barrel.
Above all, prioritizing firearm safety is paramount. Never experiment with incompatible ammunition or make modifications to your firearm that could compromise its safe operation. If you’re unsure about any aspect of firearm use or ammunition compatibility, always consult with a qualified gunsmith or firearms instructor. Prioritize safety above all else and enjoy your shooting responsibly.
