The .45 ACP needs no introduction as it has been the most reliable sidearm cartridge of our military since WWI and has a humongous fan following in the civilian gun community. Somewhere around 2002, Glock thought that the .45 ACP was too big and tried to condense the same power into the size of a 9mm round. The result was the .45 GAP cartridge. This article will present a detailed comparison of the .45 GAP vs .45 ACP to help you identify the better choice for your needs.
TL;DR: .45 GAP vs .45 ACP
.45 GAP | .45 ACP | |
|---|---|---|
Pros | Pros | |
Short OAL to suit short actions | Hard hitting power in short and medium range | |
Slightly better ballistics than the .45 ACP | Easy availability and many options for guns and ammo | |
Smaller guns suitable for women, seniors, and people with small palms | Modest recoil in full-size handguns | |
Cons | Cons | |
Very few gun and ammo options | Full-size handguns may be difficult to control for some shooters | |
Hard to find and pricey | Low capacity mags | |
Low mag capacity and better options are available | ||
Best For | Best For | |
| Self defense, hunting, and tactical applications |
History
The .45 ACP (also known as the .45 Auto) is a rimless, straight-walled cartridge designed by the legendary John Moses Browning in 1904 for his prototype semi-automatic pistol. It was the answer to the .38 Colt ammo used by the U.S Military and proved inadequate during the Philippines war. It is the longest-serving sidearm cartridge for our defense forces and is extremely popular among the civilian masses.
The .45 GAP (Glock Auto Pistol) is a rimless, straight-walled cartridge designed by Glock Firearms and introduced on the market in 2002. It hasn’t been very popular, but it offers a slight comparable advantage, which we’ll learn about further in this article.
Dimensions of .45 GAP vs .45 ACP
The .45 GAP and .45 ACP fire the same diameter bullets, but the .45 GAP has a shorter case and overall length. The .45 ACP has a case length of 0.898 inches, whereas the .45 GAP has a shorter case length of 0.755 inches.
This difference in length means that the .45 GAP holds lesser power. However, it is loaded at a 2,000 psi higher pressure to compensate for this. Additionally, the .45 ACP generally uses a large primer, and the .45 GAP uses a small primer.
Ballistics of .45 GAP vs .45 ACP
Since the .45 GAP was modeled to imitate the performance of the .45 ACP, both these rounds offer similar results in ballistics. However, the .45 GAP is a slightly better round than the .45 ACP on paper. It shoots flatter with a higher velocity and muzzle energy.
Pic Credit: Federal Premium
Barrel Life Comparison
These rounds offer a long barrel life if the weapon is serviced and maintained correctly. Many people use their .45 ACP beyond 50,000 rounds without a hitch. There have been people who have used the same barrel for their entire life without any signs of wear.
You should not usually worry about barrel life with handgun rounds. Although, for the sake of comparison, the .45GAP will have a slightly shorter barrel life (about 5%) than the .45 ACP because of its higher pressure.
Ammunition Selection
The selection for .45 GAP bullets is quite limited, and you can only opt for JHP, FMJ, or TMJ. Additionally, finding ammo is hard at small gun stores because only some stores carry it. On the other hand, the .45 ACP has many ammo options available for it. The round has been around for over a century and has a huge die-hard fan following.
Gun Selection
Glock developed the .45 GAP, and they are the only company that offers a gun for it. The Glock 37 (full-size), Glock 38 (compact), and Glock 39 (sub-compact) come chambered for the .45 GAP. As of now, no other company offers a handgun for this cartridge.
On the other hand, there are a ton of different options for .45 ACP pistols and revolvers. Starting from the venerable M1911, the options for handguns are enormous.
Relevant Characteristics: .45 GAP vs .45 ACP
.45 GAP | Specs | .45 ACP |
|---|---|---|
 Pic Credit: Wikipedia | Cell |  |
1,050 ft/s (w/ 200 gr JHP) | Velocity (at muzzle) | 835 ft/s (w/ 230 gr FMJ) |
490 ft-lbf (w/ 200 gr JHP) | Energy (at muzzle) | 356 ft-lbf (w/ 230 gr FMJ) |
1.070” | Overall Length | 1.275” |
23,000 psi | Maximum Pressure | 21,000 psi |
185-230 gr | Common Bullet Weights | 165-230 gr |
120 yards | Effective Range | 110 yards |
Key Differences Between .45 GAP and .45 ACP
To understand the usability and unique characteristics of these cartridges, it is essential to understand their critical differences. That’s because they use the same bullets, and the .45 GAP was designed to match the performance of the .45 ACP.
Size
The whole point of designing the .45 GAP was to offer a compact alternative to the .45 ACP with the same performance but a smaller size. .45 ACP handguns are full-size and bigger compared to their 9mm counterparts. Glock was trying to shorten the .45 ACP to fit it into a more compact handgun that could match the size of the smaller 9mm handgun frames.
To achieve this, Glock shortened the .45 ACP case to fit a smaller action. Hence, providing the size, handling, and light weight of a 9mm pistol with the soul-killing power of a .45 ACP.
Ballistics and Bullets
Another small but significant difference between these two cartridges is their ballistics. The .45 ACP (230 grain) has a muzzle velocity of 835 fps and a muzzle energy of 356 fps. In comparison, the .45 GAP (230 grain) has a muzzle velocity of 1,050 fps and a muzzle energy of 490 fpe.
Additionally, while the .45 ACP bullet drops 3.3 inches at 75 yards, the .45 GAP bullet drops only 2.5 inches at the same distance. However, such drops only matter a little with handgun guns, especially with powerful and heavy rounds like these. It gives you an idea that the .45 GAP performs better, even if it never took off on the market.
Chamber Pressure
Another minor difference between these two rounds is their chamber pressure. As mentioned in the previous section, the .45 GAP operates at a slightly higher pressure to compensate for its size. The .45 GAP will technically eat up the barrel fast, but it doesn’t matter, as you’ll probably never fire enough of these rounds.
Advantages of .45 GAP
- Short case and more power
- It allows you to have a more compact weapon without compromising on power
Advantages of .45 ACP
- Outstanding stopping power
- Wide variety of ammo/gun options
Use-Case Comparison: .45 GAP vs .45 ACP
Here’s a detailed use-case comparison of both these rounds to help you understand what works better in real life.
Concealed Carry
The .45 ACP has been the choice of purist gun enthusiasts for CCW and EDC applications for a long time. While there are other options that are more appropriate for concealed carry, such as the .38 Auto, and the venerable 9mm, the .45 ACP holds a special place because of its hard-hitting power.
The .45 ACP carries about 30% more power than the 9mm, and the .45 GAP is a cut above the .45 ACP with its higher velocity and energy. However, the major problem concerning .45 ACP with concealed carry is the large size of its pistols. A .45 ACP pistol that carries 7-8 rounds is a full-size pistol and not too good for concealment, especially during summer months.
The .45 GAP solves this problem with its shorter design and option for compact and subcompact models to help with concealed carry. So basically, you can carry the firepower of a .45 caliber round in a smaller handgun which helps with concealed carry and controllability.
Many subcompact handgun models are available for the .45 ACP, but the .45 GAP is only limited to the Glock 38 and Glock 39. So there’s clearly a shortage of options to choose from. Additionally, the readily available ammo and guns for the .45 ACP give it a sharp advantage over the .45 GAP.
Winner: .45 ACP
Home Defense
The .45 ACP and .45 GAP are suitable as home defense rounds. However, their penetrating power is a significant problem in this case. For example, the .45 ACP can penetrate up to 10 inches of drywall, so over-penetration is a matter of concern for both of these rounds.
While 9mm is the preferred round for home defense, the .45 ACP is also widely used by many people who prefer high power over more rounds in the mag.
As far as the .45 GAP is concerned, its small handgun size is advantageous, but the lack of ammo and only three handgun options overshadows it. On the other hand, the .45 ACP is a tried and tested home defense round with a wide range of ammo and gun options available for it.
Winner: .45 ACP
Self-Defense and Tactical Use
The .45 ACP has been the longest-serving sidearm ammunition for the U.S. Military, and it is still preferred and widely used by many police departments nationwide. The .45 GAP is not well-recognized, and there aren’t many options to fiddle with ammo and guns.
Winner: .45 ACP
Final Thoughts: .45 GAP vs .45 ACP
The .45 ACP is a venerable round that has been tested time and over again. Its best feature is the hard-hitting power that can obliterate almost any target at short range (for example, a charging black bear). The .45 GAP was designed to shorten the .45 ACP cartridge and retain its power. It certainly met its purpose but did not gain the popularity to become a widespread round.
The utter dominance of the 9mm and also the .40 S & W, which has comparable power and better controllability. The .45 GAP has faded into obsolescence today, but the .45 ACP still stands strong as a versatile handgun and submachine gun round.
Perhaps the reason was the utter dominance of the 9mm and also the .40 S&W which has comparable power and better controllability. The .45 GAP has faded into obsolescence today, but the .45 ACP still stands strong as a versatile handgun and submachine gun round.
