The most important thing to know about the 45 GAP is what it is not. It is not 45 ACP, and cannot function safely in a firearm chambered for the same.

45 GAP Ballistic Chart

Our team collected ballistic data from a multitude of popular ammunition manufacturers and assembled them in one handy point of reference. Please consult the notes below for more information on ballistic data and how we calculated ours.

Buffalo Bore

Mfr / BrandSKUBulletG1 BC / Bbl (in)
Buffalo Bore38E/20160gr TAC-XP0.133 / 4
Range (yds)Velocity (fps)Energy (ft lbs)Elevation (in)
01146467-0.2
2510844180.8
5010343800
75993350-2.8
100958326-7.9
Buffalo Bore38A/20185gr JHP0.109 / 4
Range (yds)Velocity (fps)Energy (ft lbs)Elevation (in)
01050453-0.2
259974091
509543740
75917346-3.4
100884321-9.3
Buffalo Bore38B/20185gr FMJ FN0.109 / 4
Range (yds)Velocity (fps)Energy (ft lbs)Elevation (in)
01058460-0.2
2510044141
509593780
75922349-3.3
100889324-9.2
Buffalo Bore38C/20230gr JHP0.143 / 4
Range (yds)Velocity (fps)Energy (ft lbs)Elevation (in)
0864381-0.2
258423621.5
508223450
75802329-4.6
100784314-12.7
Buffalo Bore38D/20230gr FMJ FN0.143 / 4
Range (yds)Velocity (fps)Energy (ft lbs)Elevation (in)
0865382-0.2
258433631.5
508233460
75803330-4.6
100785315-12.6

Sellier & Bellot

Mfr / BrandSKUBulletG1 BC / Bbl (in)
Sellier & BellotSB45GAP230gr FMJ0.212 / 4
Range (yds)Velocity (fps)Energy (ft lbs)Elevation (in)
0807333-0.2
257943221.7
507823120
75770303-5.2
100758294-14

Speer

Mfr / BrandSKUBulletG1 BC / Bbl (in)
Speer Lawman53979185gr TMJ0.097 / 4
Range (yds)Velocity (fps)Energy (ft lbs)Elevation (in)
01060462-0.2
259994101
509513710
75910340-3.4
100874314-9.4
Speer Lawman53980200gr TMJ0.104 / 4
Range (yds)Velocity (fps)Energy (ft lbs)Elevation (in)
0990435-0.2
259463971.1
509083660
75875340-3.7
100845317-10.3

Winchester

Mfr / BrandSKUBulletG1 BC / Bbl (in)
Winchester Super-XWC45G230gr FNEB0.182 / 4
Range (yds)Velocity (fps)Energy (ft lbs)Elevation (in)
0875391-0.2
258573751.4
508403610
75824347-4.4
100809334-12.1

Notes on Ballistic Coefficient

  • Ballistic coefficient (BC) is a numerical representation of how efficiently a bullet moves through the air. It reflects the bullet’s capacity to conserve velocity, energy, and momentum, as well as its ability to resist the influence of cross and vertical winds. When all other variables are equal (e.g. weight, muzzle velocity, etc.), a bullet with a higher BC will exhibit a flatter trajectory compared to a bullet with a lower one.
  • A bullet’s shape determines which type of BC mathematical model most accurately reflects its ballistic performance. The G1 BC is the old industry standard, and best predicts flat base projectiles’ ballistic performance. G7 BC is better suited for sleeker boat tail projectiles, which are commonly favored for long-distance shooting. We used G7 BC to calculate ballistic data when the manufacturer provided it, or when we calculated it ourselves.
  • Some manufacturers do not provide BC data, but do report their ammunition’s bullet velocities at 0 (i.e. muzzle) and 500 yards. In these cases, we calculated BC assuming the following atmospheric conditions: temperature, 59.0 °F; pressure, 29.92 in Hg; humidity, 50.0%; altitude, 0.0 feet.
  • We calculated the ballistic data on this webpage using a ballistic calculator. We calculated these data assuming the following atmospheric conditions: temperature, 59.0 °F; pressure, 29.92 in Hg; relative humidity, 50.0%; altitude, 0.0 feet.

Notes on Performance Variation

  • Real world performance invariably varies. Different lots of the same ammunition can perform differently from one another. Slight manufacturing variations affecting chamber pressure, muzzle velocity, and bullet weight can and will make two rounds from the same box of ammunition perform differently. Different rifles produce different results, especially if they have different barrel lengths (longer barrels tend to produce higher muzzle velocities, as they afford more time for the propellant to transfer its energy to the projectile). Atmospheric conditions bear significantly on ammunition performance. The shooter, of course, ultimately has the greatest influence over ammunition performance.
  • Many manufacturers do not report the lengths of the test barrels they use to record muzzle velocities. We omitted this data wherever it was unavailable at the time of writing.

What Is the Point of the 45 GAP?

45 GAP ammo headstamps lined up in a row

Several questions weighed on Glock’s collective minds during the turn of the 21st century. Prominent among them were:

  1. How can we fit ten rounds of 45 ACP ammunition into a handgun with a more compact grip?
  2. What would happen if we shortened the 45 ACP into an altogether novel cartridge, which we could easily do considering how much superfluous case capacity the old round has? And, while we are at it, fortify the case head so as to reduce the risk of neck blowouts?
  3. Wouldn’t it be nice if we could manufacture handguns chambered for a cartridge of our own design, as opposed to stamping the names of ammunition developed by other companies on their slides?

This line of thinking compelled Glock to develop the 45 Glock Auto Pistol (GAP), which they began producing in 2003. They have not introduced another new cartridge since.

An Ill-Fated Idea

A Glock 45 GAP pistol and ammo at a shooting range

Glock’s reasoning may have paid off if not for the expiration of the Assault Weapons Ban one year after the 45 GAP’s arrival on the market. The federally imposed ten-round limit on newly manufactured handgun magazines vanished overnight, which meant the shorter and narrower 9mm (which easily exceeds ten rounds in a full-size handgun’s magazine) could rise further to prominence. Demand for magazines that pack ten rounds of .45 caliber ammunition dropped in turn.

All of this is to say that the 45 GAP never won mainstream appeal. Some law enforcement agencies, notably the Pennsylvania State Police and the Florida Highway Patrol, adopted (but have since abandoned) it. Glock continues to produce the Glock 37 pistol, although we’d hesitate to recommend it to someone who isn’t (A) a cop (or retired cop) who is already familiar with the 45 GAP, or (B) an enthusiast who wants to be able to fire an increasingly niche handgun cartridge, and doesn’t mind that its performance is virtually indistinguishable from an incomparably more popular alternative.

45 GAP vs. 45 ACP

Just how similarly does the 45 GAP ammo perform to the 45 ACP? We’re glad you asked, or else we would have created this comparison chart for no reason.

Velocity (fps)Energy (ft lbs)Elevation (in)
Range (yds)025507510002550751000255075100
45 GAP 185gr TMJ1060999951910874462410371340314-0.210-3.4-9.4
45 GAP 200gr TMJ990946908875845435397366340317-0.21.10-3.7-10.3
45 GAP 230gr FMJ807794782770758333322312303294-0.21.70-5.2-14
45 ACP 185gr TMJ1050991944904869453404366336310-0.210-3.4-9.5
45 ACP 205gr SHP970941916892870428403382362345-0.21.10-3.7-10.2
45 ACP 230gr TMJ830812794777761352336322309296-0.21.60-5-13.6

As you can see, the 45 GAP closely mimics the 45 ACP. It essentially mirrors the older round’s performance when the two are loaded with bullets of the same weight.

And that’s the point. The 45 GAP’s ballistics weren’t intended to outclass those of the 45 ACP. Its chief appeal is its shorter overall length, which facilitated the design of more ergonomic handguns without forfeiting stopping power. Had ten rounds remained the federally imposed limit on handgun magazine capacity, then the 45 GAP very well may have caught fire. But since that is no longer the case, the 9mm was able to ape a large portion of the market that Glock had (wrongly) presumed would continue existing.

In summary, the 45 GAP is a fine cartridge in its own right. Its virtually identical performance to that of the second most popular semi-automatic handgun cartridge in the United States makes it suitable for personal protection, and familiar to anyone who already knows their 45 ACP. It was simply designed to fill a niche that ceased to exist shortly after its introduction, and grows increasingly irrelevant with each passing year.