What is this gibberish about 45ACP not shooting flat?

[ElectrikKoolAid]

A bullet dropped from your hand and a bullet fired (parallel to the ground) will both hit the ground at the same time.

The vertical pull of gravity is the same no matter what the horizontal speed of the object is. Likewise, a small bullet and a large bullet dropped from your hand will both hit the ground at the same time, as the acceleration of gravity acts on all objects equally.

The 9mm, moving from the muzzle almost 30% faster than a .45, covers the distance to the target in less time. This gives gravity less time to perform downward movement, hence less "drop".

The faster a bullet, the "flatter" it's trajectory for a given distance.

 

[Ben86]

People tend to over state the drop of a .45 bullet. It's more than other, lighter calibers, but not by much. The important thing is that you know how much it drops at X range and know how to compensate for it accordingly.

 

[Gryffydd]

Caliber 25 yard 50 yard 100 yard
45 ACP + 1.4" -0- -13.8"
10 mm + 0.4" -0- - 6.5"

No contest.

WOW! 7 WHOLE INCHES!!

The point is, there is no practical difference between the two given the typical application of such pistols.

If 100 yard squirrel hunting with defensive pistol calibers is high on your priority list that 7" might mean something. Otherwise it's a moot point.

 

[tipoc]

Usually what folks mean, the practical part anyway, when they say that a certain round is "a nice flat shooting round" is that you won't have to adjust your sights or "hold over" the target in order to hit it for out to a longer distance. And when they say something is "rainbow like" they are exaggerating some but indicating that they have to adjust their sights some to hit what they want to at a longer distance like 100 yards.

There are commonly two ways to measure, or illustrate the arc a round makes in it's flight, and they all arc some.

One way is called the bullet drop. This figures like this...If you stood on top of a ladder and held a gun perfectly horizontal to the plane of the earth, and you were standing in a vacuum, and you shot that gun and the round traveled at a certain speed how far would the bullet fall horizontally by the time it reached a certain distance. That figure would be the bullet drop.

So the bullet drop at 100 yards for a 125 grain Cor Bon load for the 38 Super traveling at 1350 fps would be - 11.4 inches.

For a 230 gr. Hornady TAP round from a 45acp going at 950 fps from the muzzle the drop at 100 yards would be -20.4.

So you'd want to adjust some for the 9 " difference between the two.

tipoc

 

[tipoc]

I mentioned two ways and the second way is sometimes more useful to see the arc. The second way is the Mid Range Trajectory. It works like this...In the actual world we don't hold our guns flat and parallel to the face of the earth we aim them upward a bit and at longer distances actually lob in our rounds, like mini artillery. If your gun is zeroed in to hit where you want at, say 100 yards for hunting at 50 yards it will always be shooting high. How high is the mid range trajectory.

So our 230 gr. Hornady TAP 45acp round moving at 950 fps in a gun sighted in for 100 yards will be 6." above the point of impact and line of sight at 50 yards.

Our 125 gr. .38 Super load from Cor-Bon at it's 1350 fps and sighted in for 100 yards will be 3.1" high at 50 yards.

2.9" isn't much of a rainbow of difference. But if we use a slower 45 acp round like 230 gr. at 850 fps. it's 6.6" high at 50 yards.

A faster 115 gr. load for the .38 Super from Cor-Bon at 1425 fps would be 2.9" high at 50 yards.

So that is the "flat shooting" .38 Super and the "rainbow like" .45acp.

A lot of these terms like "rainbow like" come to us from rifle shooting and rounds like the 45-70 and bigger.

These particular figures I've taken from Bob Forker's useful book "Ammo and Ballistics".

tipoc

 

[Snowdog]

If you stood on top of a ladder and held a gun perfectly horizontal to the plane of the earth, and you were standing in a vacuum...

I know you weren't trying to be funny, but I certainly couldn't get the thought of firing a pistol from a ladder in a vacuum out of my head after reading that.

However, you explained it well. Good info there, thanks!

 

[oldfool]

yeah, weight has nothing to do with it, velocity does
but I am mostly waiting for Jack O'Connor and Elmer Keith to jump on in this one

 

[LiveLife]

I certainly couldn't get the thought of firing a pistol from a ladder in a vacuum out of my head after reading that.

Was watching a movie once where they had a gun fight in the vacuum of space. The bullet would travel in a straight line without loss of velocity until it countered a gravitation pull. Imagine sniping at the surface of the moon from a space craft and hitting the target at the same velocity and trajectory as point of aim.

 

[Cards81fan]

WOW! 7 WHOLE INCHES!!

The point is, there is no practical difference between the two given the typical application of such pistols.

If 100 yard squirrel hunting with defensive pistol calibers is high on your priority list that 7" might mean something. Otherwise it's a moot point.

You wouldn't believe how fierce Oklahoma's fox squirrels can be...

 

[Magnumite]

"Quote:
Caliber 25 yard 50 yard 100 yard
45 ACP + 1.4" -0- -13.8"
10 mm + 0.4" -0- - 6.5"

No contest.

WOW! 7 WHOLE INCHES!!

The point is, there is no practical difference between the two given the typical application of such pistols."

There is a big difference. Very practical difference if you actually do practical shooting at 100 yards or meters, depending on the game. A Hunter's Pistol metallic silhouette ram has a body approximately 8 inches deep. So with these settings, using the 10mm, you'd have to hold half a body over to make consistant hits. With the 45, you'd have to hold 1 1/2 bodies over the ram. Now your sights are covering up the target - how are you going to see it to align the sights well enough to hit it? Okay, you say, hold the front sight up over rear just a bit. Repeatable...not much with consistency...unless you have gold bars or such on it, then with light at some angles, you lose the definition on the bars because of glare.

So if you mean practical at 100 yards to mean a four foot x 18" effective target, with the 45 - it is still the difference between a chest shot and a gut shot, or a gut shot and a thigh hit or a miss between the legs - depending where you were in your wobble zone when the shot broke.

In combat you use what you have to make it work. The OP likes shooting at longer ranges. No problem, he likes the longer ranges and has adjusted his sights to accomodate the longer ranges...he is matching his equipment to the application. But with standard POA/POI settings, you're always holding over way out there. That is where the ballistics come into play.

 

[Gryffydd]

There is a big difference.

I'm sorry, it's just not a big practical difference when you have to go for something nobody really does with either of those calibers to prove the difference. I honestly couldn't care less about the trajectory of either of those rounds past 25-50 yards. If I want to shoot farther than that I'll use one of my revolvers--or you know...a rifle.

 

[Magnumite]

The statement was made there was no practical difference between those two calibers. The OP does it with those calibers. 2 times the drop is not a big difference? And the issue wasn't using another caliber, it was using those calibers. It is such a big difference when we shoot long range, many of us make sight adjustments so we have the sight picture we need...because using hold over/under doesn't work well even with practical size targets. So if a gun were used without adjustable sights, a flatter shooting gun would mean less hold over/under to make hits. Just the width of your front sight on these guns covers 4 to 20 inches at 100 yards, dependent on front sight width and distance from the shooter's eye.

I don't take my 45 1911's much past 50 meters, I don't see it as a practical gun past that. But I do shoot long range...out to 200 meters with more appropriate calibers and guns and I can tell you trajectory is a big deal.

 

[KodiakBeer]

Not a good argument because you could simply shoot 165 or 180 grain 45 acp's and effectively remove any difference in bullet drop. And, you'd do so with lessened recoil and faster follow up shots.

 

[JohnBT]

"when you have to go for something nobody really does"

I shoot handguns at 100 yards and I'm a nobody? What are you talking about?

John

 

[Magnumite]

lighter weight bullets typically shoot lower, increasing the need forhold over. If one were doing that, it's simpler to make sight adjustments.

John, he said I was nobody, too. LOL

 

[Thorgrim]

I can understand the argument that a flatter-shooting cartridge increases practical accuracy for most shooters because it makes misjudging range less critical. When I varmint hunted I mostly shot a .257 Weatherby because civilian-available rangefinders weren't very good at the time, and neither was I concerning ranging in that deceptively rolling country we hunted. The hot .257 was very forgiving if I misjudged the range a bit.

At the same time, a man shooting a "blooper" who knows his gun, sights, and can estimate range well can consistently outshoot a man with a flat-shooting cartridge who doesn't possess those skills. I'm not taking sides here - but look up "Billy Dixon Adobe Walls" sometime and draw your own conclusions; many of the accounts agree that he shot a Cheyenne warrior off his horse at over 1,500 yards with a buffalo rifle using open sights ... and he called the shot before he took it.

And it doesn't make any difference whether your pistol shoots flat or not if it isn't accurate, I'm with Townsend Whelen on that topic.

 

[Gryffydd]

I shoot handguns at 100 yards and I'm a nobody? What are you talking about?

I never said anything about shooting handguns at 100 yards. What are you talking about?

What I was referring to was shooting at 8" targets with fixed-sight automatic pistols chambered in basically service calibers. And by "nobody" I obviously meant the hyperbolic "nobody" which is in fact "almost nobody", as there are a lot of people that go around doing things that "nobody" does, like shooting ground hogs with 50 BMGs, or hunting squirrel with a .375 H&H.

One might as well argue about the difference in trajectory between a 35 Remington and a 30-30 at 800 yards when fired from an open-sighted lever gun.

 

[JohnBT]

You quoted a post about shooting at 100 yards and replied to it.

You appeared to be referencing the 100 yard range when you went from "past 25-50 yards" to the statement about using a rifle for "farther than that."

"I honestly couldn't care less about the trajectory of either of those rounds past 25-50 yards. If I want to shoot farther than that I'll use one of my revolvers--or you know...a rifle."

That's what I'm talking about. Remember now?

 

[Gryffydd]

Hey John, I'm not sure you realize this, but a revolver IS a handgun. So my post that you quoted says quite clearly that I wasn't referring to "handguns at 100 yards." Yes, the post that I quoted did talk about shooting handguns at 100 yards. Specifically, 8" tall targets, and given the context, 8" tall targets being shot with fixed sight service pistols.