45 GAP Ammo icon

45 GAP Ammo For Sale

Live Inventory
The .45 Glock Automatic Pistol (GAP) cartridge was designed to be shorter in length than a .45 ACP, while maintaining a similar level of energy. Shorter than a standard 9mm cartridge, the .45 GAP will generate up to 600 foot pounds of energy at the muzzle. Learn More
per page
  1. Magtech 45 GAP Ammo - 1000 Rounds of 230 Grain FMJ Ammunition


    2 In stock now

    1 2 3 4 5 6 7 8 9 +10
    Bullet type FMJ
    Primer Type Boxer
    Casing Type Brass
    Condition New
    Muzzle Velocity 837 FPS
    Muzzle Energy 358 ft lbs
    • 1000 Rounds
    • 75¢ per round
    • Made by Magtech
  2. Magtech 45 GAP Ammo - 50 Rounds of 230 Grain FMJ Ammunition


    3 In stock now

    1 2 3 4 5 6 7 8 9 +10
    Bullet type FMJ
    Primer Type Boxer
    Casing Type Brass
    Condition New
    Muzzle Velocity 837 FPS
    Muzzle Energy 358 ft lbs
    • 50 Rounds
    • 49¢ to 80¢ per round
    • Made by Magtech

History of 45 GAP Ammo

In 2003, .45 Glock Automatic Pistol (GAP) ammunition was introduced as the first cartridge to have the Glock name attached to it. Designed as a rimless, straight-walled round, the .45 GAP shares the same bullet diameter of the popular .45 Automatic Colt Pistol (ACP), a hefty .451 inch. For the .45 GAP, the bullet sits in a .755-inch casing (the same length of a 9mm shell), giving the full ammunition an overall length of 1.070 inches.

Although it’s a big bore bullet, the ammo uses a small pistol primer with a maximum pressure of 23,000 pounds per square inch (psi), making it a great option for self defense and concealed carry. Since its conception, the cartridge has proved itself completely capable as both a duty cartridge and one designed for personal protection, as it’s accurate, efficient, and reliable – exactly what one would expect from Glock, the company that has provided more United States law enforcement handguns over than last two decades than any other firearms manufacturer.

Development of the .45 GAP

Starting in the early 2000s, Glock set out to make a .45 caliber ammunition that could be used in a compact handgun that didn’t have an oversized grip. This would allow the handgun to be carried concealed and used by most shooters without issue. In 2003, Glock created a new pistol, the Glock 37, and collaborated with the ammunitions manufacturer Speer to create its intended ammo.

To meet their needs, Glock told Speer what it desired in the new ammunition’s specs. Glock wanted a .45 caliber bullet in a case no longer than that of a 9mm Parabellum or the .40 S&W. They also wanted a cartridge that could fit within a grip no larger than what they had in their Model 17 or 22 pistols, ensuring that, regardless of the size of the shooter’s hand, they would be able to manage the pistol.

Through this Glock/Speer partnership, the .45 GAP was created, with bullets that range from 165 grain (gr) to 230 gr (although the best ballistic performance tends to be with bullets weighing between 185 to 200 gr). On average, .45 GAP ammo generates about 400 to 500 foot pounds of energy (ft·lb) at the muzzle, though some loads reach up to 600 ft·lb and beyond.

Glock's goal in developing the .45 GAP was to provide as much energy as the .45 ACP – or more – while reducing the grip distance from front to back and side to side. In this way, .45 caliber handguns could become more accessible to shooters of small stature. And with the .45 GAP, they succeeded in all aspects.

Response to the .45 GAP

Upon its initial release, the public’s response to the .45 GAP was generally positive and .45 GAP pistols were produced by a few firearm manufacturers other than Glock. However, as time went on, many of these firearms were discontinued and, currently, Glock is the only manufacturer of handguns chambered for .45 GAP ammunition.

Where the .45 GAP has seen significant success is with the law enforcement community. Five state law enforcement agencies having chosen the Glock 37, which is chambered in .45 GAP ammo, as their primary duty piece. This decision is based on the fact that the cartridge has similar power and performance when compared to the .45 ACP, yet in a more compact and easier-to-handle frame. When compared to the 9mm, the .45 GAP offers more stopping power.

The New York State Police replaced their Glocks chambered in 9mm for Glocks chambered in .45 GAP, and state agencies in Florida, Georgia, South Carolina, and Pennsylvania have set aside their .40 S&W pistols for the .45 GAP Glock 37.

The Glock 37

The Glock 37, the first handgun chambered for the .45 GAP, previewed at the 2003 SHOT show in Las Vegas, and was released that fall. Using Glock’s standard frame, the Model 37 was a leap for the future of big bore technology. This pistol significantly reduced muzzle flip and the high recoil often seen in big bore ammunitions, making the firearm and ammo easier to handle and shoot than other large bore ammos.

Even though the Glock 37 is a full-sized handgun, it’s still much easier to carry concealed than a pistol chambered for the .45 ACP – more along the lines of full-sized 9mm. Because of its smaller size and ease of use, police departments and highway patrol agencies across the country have opted for this firearm.

The first was New York State Police. When Superintendent Wayne Bennett publicly announced the decision that the agency was going to purchase over 5,000 of the new Glock pistols, he gave multiple reasonings for the decision to go with the Glock 37, including:

  • The .45 GAP pistol fit in most hands, even those of women
  • The firearm was manageable to those with limited firearm experience
  • It was easy to shoot and practice with (user friendly)
  • The .45 GAP ammo has strong ballistic force

Who Makes .45 GAP Ammo?

Because .45 GAP ammo isn’t as popular as other cartridges, not all ammunition manufacturers make the round, although many still do. Of course Speer, who collaborated with Glock on the ammo’s initial release, continues to make the ammo, but only in its Lawman training rounds. While the original Speer 185 gr Gold Dot JHP has been discontinued, the Lawman rounds are designed to feel and function like a self-defense round without the added price.

Other manufacturers who make .45 GAP ammo include:

  • Federal Ammunitions: Although Federal has discontinued making .45 GAP ammo, many of its rounds are still available at retail giants, local gun stores, and online ammunition retailers. Shooters can find this ammo in both Federal’s American Eagle and Personal Defense Hydra Shok lines.
  • Magtech: Magtech makes a general Glock .45 GAP ammo. It features a 230 gr, full metal jacket (FMJ) bullet that can be used for target shooting or training.
  • Remington: Remington makes .45 GAP cartridges in its UMC line. This round has a 230 gr FMJ bullet that is designed for plinking or target practice.
  • Winchester: Winchester manufactures multiple rounds in the .45 GAP caliber. The company offers 230 gr FMJ bullets (great for target shooting and training) as well as 185 and 230 gr jacketed hollow points (JHP). The JHP rounds are specifically designed for self defense and supply the shooter with more stopping power than other ammunitions in the caliber. Winchester also offers .45 GAP ammo in its Super X Winclean line, which eliminates any airborne lead while shooting.

Types of .45 GAP Ammo

While multiple manufacturers make .45 GAP ammunition, it’s obviously not as popular as more common rounds. In most cases, when looking for cheap .45 GAP ammo, shooters can opt for either full metal jacket (FMJ), total metal jacket (TMJ), or jacketed hollow point (JHP) ammunition.

FMJ ammo features a lead bullet encased in a harder metal, typically copper, which helps the projectile keep its shape during its flight to impact. These rounds are often used in target shooting and backyard plinking, but can also serve as self-defense rounds.

Total metal jacket ammo, much like FMJ, has a lead bullet encased in a harder metal. While the visible part of the FMJ bullet is covered, lead is often exposed within the ammo’s casing. With a TMJ bullet, the entire projectile is wrapped in copper. This limits the shooter’s exposure to lead and is required for shooting in some indoor ranges throughout the U.S.

JHP ammo also has a lead bullet encased in a copper jacket, but instead of a spherical projectile, this bullet has a hollow point in its interior – allowing for greater expansion on impact, a larger entrance wound, and reduced risk of over-penetration. Because of .45 GAP ammo prices, these rounds are often more expensive and used for self defense and as duty cartridges, which means they’re less likely seen at the range.

The .45 GAP vs. .45 ACP

When it comes to .45 GAP vs. ACP, both similar ammunition calibers, there’s no doubt they share many qualities. After all, they’re both a rimless, straight-walled round that have the same sized bullet (.451 inch) that was designed to be shot from a semi-automatic handgun. But it’s not the size of the bullet that makes the ammunitions different, it’s the size of the casing and overall round.

When Glock set out to make a more manageable .45 caliber, they knew they wanted a gun with a smaller grip than the .45 ACP allowed. The only way to accomplish the task was to make a .45 ammo that was significantly smaller the the ACP. When the final .45 GAP cartridge released, it came in a .755-inch case, which is almost the exact same size as the 9mm shell. This smaller case was just over one-eighth inch shorter than the .898 .45 ACP case, but thicker to handle the increased load of the ammunition. In overall length, the .45 GAP saw a significant decrease from the 1.275-inch .45 ACP to its 1.070-inch size.

What the .45 GAP lacks in size, it makes up for in pressure. According to the Sporting Arms & Ammunition Manufacturers’ Institute (SAAMI), the maximum pressure for the .45 ACP is 19,000 psi, while the .45 GAP can reach 23,000 psi, the same max pressure for a .45 ACP +P load. Even with the small pistol primer (compared to the ACP’s medium to large primer) the pressure difference makes the smaller ammunition’s performance meet that of the ACP, and in some cases, exceed it.

For instance, when comparing performance specs, a .45 ACP 230 gr FMJ bullet can reach a velocity of 835 feet per second (fps) and a muzzle energy of 356 ft·lb. This same sized bullet in a .45 GAP cartridge can reach a velocity of 940 fps and a muzzle energy of 451 ft·lb.

What’s more, the firearms chambered for the .45 GAP have a smaller grip, making them easier to hold for women, seniors, and men with small statures. The smaller grip leads to an easier-to-conceal firearm that can hold more rounds than a similar sized gun chambered for the .45 ACP.

Where this ammunition fails is that, although it’s accurate and reliable, it’s never caught on with the American public. It’s often seen as direct competition to the .45 ACP, which is not only one of America’s favorite rounds, but its baby. The cartridge was created by John Browning nearly 100 years before the .45 GAP and has been chambered in some icon firearms – including the Colt M1911, perhaps one of the most popular personal firearms in the country.

Because the .45 GAP never reached a mainstream fan base, the firearms available for the Glock cartridge are extremely limited, especially if the shooter isn’t a Glock fan. And since cost is often determined by supply and demand, .45 GAP ammo prices are higher than those for the .45 ACP.

.45 GAP Pistols

Sure, Glock makes handguns chambered for the .45 GAP. Along with the Glock 37, which is a full-sized semi-automatic pistol, the Austrian company also makes the Glock 38, which is a compact version, and the Glock 39, which is considered a subcompact pistol.

Currently, Glock is the only firearms manufacturer that’s making pistols for this caliber. Other .45 GAP pistols can be found at used gun stores, but they’re few and far between. Some of the most common .45 GAP firearms include the:

  • Para LDA in .45 GAP
  • Springfield Defender in .45 GAP

Although they don’t necessarily offer a firearm in .45 GAP ammo, Bond Arms does offer accessory barrels in the caliber, which allows shooters to modify their existing Derringers.


What is 45 GAP ammo?

The .45 Glock Automatic Pistol (GAP) was the first ammunition to have the Glock name. Glock wanted a round with a bullet the size of the .45 ACP, but with the case dimensions of the 9mm or .40 S&W. This allowed Glock to create a compact handgun small enough to carry concealed and have a manageable grip, but with enough power to be used as a duty cartridge. They collaborated with Speer for the ammo and released the handgun for it, the Glock 37, in 2003.

What does GAP stand for in 45 GAP ammo?

The GAP in .45 GAP stands for Glock Automatic Pistol. It’s the first round to have the Glock name attached to it.

What is the difference between .45 GAP and .45 ACP ammo?

The main difference between the .45 GAP and the .45 ACP is the size of the casing. The Glock casing is over one-eighth inch shorter than the Auto, but thicker so it can handle the increased load. The smaller cartridge is loaded to a higher pressure, which allows it to reach, and sometimes exceed, the .45 ACP’s ballistic performance.

Which is the most powerful ammo between a .40 Cal, 10mm, .45 Auto, and .45 GAP?

When comparing the .40 Cal, 10mm, .45 Auto, and .45 GAP rounds, the 10mm is the most powerful. The cartridge’s muzzle energy reaches levels as high as 768 foot-pound force and velocities as high as 1,600 feet per second.

How much does .45 GAP ammo cost?

The cost of .45 GAP ammo depends on the type of ammunition purchased, as well as the quantity. Bulk ammo is likely to be more affordable. On average, you can expect .45 GAP ammo to start around $0.40 for a full metal jacket round, and $0.81 for a specialty jacketed hollow point.

.45 GAP Ballistics: Chart of Average .45 GAP Ballistics

When firing .45 GAP ammo, shooters can expect consistency and accuracy. And as for .45 GAP ballistics, there’s a range of performance, depending on what type of ammunition is being shot.

Note: This information comes from the manufacturer and is for informational purposes only. The actual ballistics obtained with your firearm can vary considerably from the advertised ballistics. Also, ballistics can vary from lot to lot with the same brand and type load.

45 GAP Bullet WEIGHT Muzzle VELOCITY (fps) Muzzle ENERGY (ft. lbs.) Mid-Range TRAJECTORY (in.) Barrel Length (in.)
  Muzzle 50 yds. 100 yds. Muzzle 50 yds. 100 yds. 50 yds. 100 yds.  
165 Grain 1007 936 879 372 321 283 -1.4 -11.8 5"
185 Grain 1090 970 890 490 385 320 1 4.7 5"
230 Grain 880 842 n/a 396 363 n/a n/a n/a n/a
Molly Carter
Written by
Molly Carter

Customer Reviews

  • Jordan said:


  • Harry said:

    I'm in no way an expert but I've fired 100 rounds of this ammo so far and am pleased with my purchase 4 inch grouping at 10 yards with my glock 37 which isn't bad for a 45. The ammo does smoke a little but there were no misfires, jams or duds.