Accuracy, 9mm vs.45acp?

Question

In guns of equal craftsmanship, barell lenth, etc, which caliber has better accuracy at the same range. Also, does either have an advantage over the other at longer ranges?

Answer 1

If you had two otherwise identical customized competition race guns fired by ultrastable, recoil-insensitive robotic platforms, one in .45 ACP and one in 9mm Luger, the most accurate one will probably be the 9mm Luger.

Why? In the 9mm caliber, you can have a relatively long, boat-tail bullet (weight of 147 grains.) While the 147 grain bullet is worthless as a self-defense load (it tends to grossly overpenetrate,) it has a better ballistic coefficient and higher sectional density than the heaviest bullet you could safely stuff into a .45 ACP case. The boat-tail also offers a better aerodynamic profile than the usual flat-based pistol bullet (which is why so many rifle bullets have them.) What all that jargon means is that the 9mm bullet will stabilize better in flight, for greater accuracy potential.

The 9mm will drive our 147 grain boat-tail at 1000 ft/sec (more if we went with +P or NATO pressures, but this probably violates the spirit of the question.) The .45 ACP will drive a 230 grain round-nosed bullet at 900 ft/sec. Sighting them in at 50 yards, the .45 ACP will have a mid-trajectory rise of 1.15", while the 9mm will have a mid-trajectory rise of just 0.9". In this instance, we're not using the lighter .45 ACP bullets, because they're, relatively speaking, short and fat, having an aerodynamic profile closer to that of a plain ball than the longer, heavier bullets.

If we follow the bullets out to 100 yards and add in a 10 MPH crosswind, the 9mm bullet drops a bit over 19", compared to the over 23" drop of the heavier, less aerodynamic .45 ACP bullet. However, the heavier .45 ACP bullet resists drift, having drifted only 2.43" in the direction of the crosswind, compared to 2.69" for the lighter 9mm bullet. However, the .45 ACP has only dropped 39 ft/sec of velocity, whereas the 9mm has shed 79 ft/sec velocity (the heavier bullet carries greater momentum and inertia. So even though it's less aerodynamic, it resists slowing down better.) And since the .45 ACP bullet is heavier, it will penetrate better at range than the 9mm bullet (as it carries greater energy and momentum.)

Answer 2

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Answer 3

There is a difference in accuracy between 9mm and .45ACP, but the difference is related to recoil signature and not the mechanical accuracy of the cartridge. The short answer is: 9mm is more accurate at any given range and has a flatter trajectory over longer ranges.

Both 9mm and .45ACP rounds have greater mechanical accuracy than most shooters can match with their own accuracy. The reason why most people shoot better with the 9mm is because recoil and muzzle jump are more controllable.

Does less recoil and more shooter accuracy mean less "stopping power" in the 9mm? This depends on a huge number of variables related to the exact load you happen to be using. At long ranges, however, the 9mm will always have the upper hand because of A.) flatter trajectory and B.) More ability to penetrate the target. .45ACP rounds fired at distances over 75 meters have literally been known to bounce off their targets. I have watched this happen.

I carry a 9mm on duty as a military police officer, and wish we had access to the more accurate and powerful civilian loads. These are two of the most accurate hunting and personal defense loads you can get:

Hornady XTP 9mm 124Gr.
Hornady XTP .45ACP 230Gr.

Remington Golden Saber hollowpoints also use a bullet design feature known as a "driving band" to create phenomenal accuracy. Both the 9mm and .45 "+P" loadings in the Golden Saber line have good accuracy and flat trajectories for long range shooting. But...you guessed it: Recoil comes along with that performance. Good luck.

Answer 4

Both will be as accurate as the shooter. The .9mm has the capability of shooting farther due to the lighter, slimmer projectile. All things equal, the .45acp is the better man-stopper due to the sheer broadness & weight of the bullet. A 115 grain or 124 grain .9mm +P+ will tend to be a better stopped than a full-metal-jacket, standard load .45acp. It will also shoot further because the heavier .45 bullet will drop more, as it is not only heavier but it moves slower. What can you throw further, a cinder block or a ball bearing released from a slingshot?

Returning to your original question, both the .9mm & the .45acp are good, accurate cartridges. The .45 will drop more than the .9 quicker because it is a heavier, slower moving bullet but the cognizant handgunner will know to compensate for this. Therefore the .9 will generally shoot further because it is slimmer, lighter and faster than the .45acp. This does NOT make the .45 the lesser gun.

I hope that helped.

H

Answer 5

A 230gr .45 ACP slug will be more accurate than a 115-124gr 9mm due to the shallow base of the latter rounds and the lack of sectional density. Have you ever noticed how scant the rifling is in a .45ACP barrel? 9mm need deeper rifling for better stabilization. However, I would consider 147gr 9mm to be equal to or more accurate than a 230gr .45 slug.

Answer 6

The .45 would suit your needs in most instances better then the 9mm. The 9mm has difficulties matching the consistancy of the .45 and guns that fire the 9mm tend to be much more picky when it comes to finding a particular manufacturers load that'll hold a decent grouping. Sure, you may get slightly longer range with the 9 but it's ability to do much damage past the range distance between the two rounds would probably not be substantial. As the military is AGAIN finding out, bigger is better when it comes to actual stopping power.. (Note the change from 5.56 to 6.5mm in the M4 and the search for a "new" .45 to "supplement"/replace the 9mm sidearm)

Answer 7

All things being equal the 9mm will always shoot tighter groups due to the fact that it has a smaller diamitor than the 45 acp.

Now at longer ranges the heavier bullet weight of the 45 will carry more momentem and power than a 9mm but the lighter 9mm will shoot flatter further than the 45.

Answer 8

If we took human error factor out of the equation and used quality weapons and ammo.
The 45 ACP would be the better in accuracy, but not range.
There the 9 mm has an advantage at extended range.

The 45 ACP is a large slow moving subsonic bullet that suffers less affect from wind drift.
The 9 mm is a lighter and faster in most cases is super sonic that will be more affected by wind drift.

But both rounds are very good self defense rounds.
And the variations of accuracy would not be that great but in range there are substantial differences.

That my opinion and I am a fan of both rounds.

D58

Answer 9

The .45 ACP round if fired from match grade guns, with match grade ammo, can literally drive tacks. At 75 ft. groups can be had as small as 1-l 1/2 " at the hands of a gifted shooter. 9mm on the other have can never achience this level of accuracy, which is why 9mm is not used in pistol matches, except for police matches.

Answer 10

the 9 on all counts except knockdown power the 45 falls out of the barrel @ about 940-50 fps the9 would have a much flatter trag. but a full hit with a 45 it aint getting up 45 at long range depends on what you call long 35 or 100 yds no handgun is a tack driver even competion gun some people claim dead on accuracy look at the hits on a ram at competion range its hit allover if at all reg carry gun 30 yds aint bad 50 your hoping 100 your dreaming