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And where a lot of the confusion arose in the other thread was interior vs exterior ballistics, and rifles vs handguns.


With a rifle, the bullet spends time in the bore, but it will be traveling faster than a handgun bullet, and the weapon itself will be better controlled while the round is still in the bore. The sights will be higher than the bore axis (with some rifles, a loooong way; see M16 irons), so the sights and the bore axis will converge at some point...actually at two points, as the bullet will rise above the line of the sights, and then drop again.


Handguns are a different deal. If you lay a revolver down, and place a ruler across the top of the sights, you'll see that the bore axis and the sight line diverge. If the gun remained static at the moment of firing, the bullet would strike low. We are assuming that the gun is correctly zeroed already, so we're not going to solve the problem by raising the back sight.


So, why then, doesn't the bullet strike low, especially since gravity will pull it down even further after it leaves the bore? That is the real question.


And I'll leave it at that; how is the bullet getting up to the sight line if their paths should be diverging?
Moon
 

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The issue is more noticeable in rifles for two reasons:

1- The barrel is longer and the sights are often higher.

2-Longer distance shooting is not generally an issue with a hand gun.

The discussion virtually never happens with handguns. But ballistics is ballistics. Bullets are lobbed and follow an arc.

I have laid out multiple hand guns. In every case the sight alignment seems close to level. It’s hard to tell with lack of any accurate real measurement.

But I have used laser bore sights numerous times. If you were to use one, you can see the arc. Because a close range the laser will be low. Back up....the sights and laser are on top of each other. Back up further and the laser goes high this showing the arc.

In actual shooting, I have noticed that bore sight doesn’t work all that well. The actual point at which the two converge is different. I suspect that is because the gun is not held in a vice and the bore sight can’t account for gravity and other forces.

I have not tried this with an old revolver....however. I have some single actions with high front blades.
 

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It's different with rifles because their reaction in recoil is different.
And the laser boresight will not show an arc; it will show a straight line. At some point the bore axis and the sight axis intersect, but both will be straight lines. The bullet path will not.

We are consistently confusing internal and external ballistics.
I agree laser borsights don't give a dead nuts on zero; they'll get you close and save you ammo, but they can't be trusted as a final zero before you go afield. But it is still a rifle.
Moon
 

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I don’t believe that recoil has to to with shot placement as far as point of aim. If that were true you would have to handle the recoil the same every time to get consistent shot placement. Which is highly unlikely. The bullet obviously travels fast enough to exit the barrel before the recoil has an effect.

Now flinching or tensing up in anticipation of the recoil is different because it’s being done before or ad the trigger is pulled and the result is moving the firearm off target.
 

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I don’t believe that recoil has to to with shot placement as far as point of aim. If that were true you would have to handle the recoil the same every time to get consistent shot placement. Which is highly unlikely. The bullet obviously travels fast enough to exit the barrel before the recoil has an effect.

Now flinching or tensing up in anticipation of the recoil is different because it’s being done before or ad the trigger is pulled and the result is moving the firearm off target.

I agree and numerous other sites including ballistics and engineering professionals said exactly the same thing.
 

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Ballistics is ballistics. It’s all the same.....from 22 to Artillery. Everything lobs out at the target to one degree or the other.

Moon, you are just confusing the topic
 

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You really need to stop posting on this subject. Ballistics is ballistics.

And thank you so much for telling me to shut up.
Moon
 

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I don’t believe that recoil has to to with shot placement as far as point of aim. If that were true you would have to handle the recoil the same every time to get consistent shot placement. Which is highly unlikely. The bullet obviously travels fast enough to exit the barrel before the recoil has an effect.

Now flinching or tensing up in anticipation of the recoil is different because it’s being done before or ad the trigger is pulled and the result is moving the firearm off target.

Jaake, you are exactly right about flinch or heeling affecting the impact, of the shot, and it occurs before the sear breaks.


And you are entirely wrong about handling the recoil the same every time. Good shooters try to do just that; hold the gun precisely the same every time. They try for a firm, consistent grip, so that the gun recoils in their hand the exact same way every shot. It is also why a consistent follow-thru is necessary. It is one of several crucial difference between good shots and mediocre ones.



If it didn't matter, we could hold the gun differently each time, tightly, loosely, whatever, and the bullets would strike the same place anyway. But such is not the case.


I will agree that there are so many variables when firing a handgun unsupported that it is far more difficult to hit things. It is why rifles are more accurate than pistols.
Moon
 

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Rifles are more accurate because they have longer sight radius and higher velocity. The issue of stability is separate. You can hold a rifle stable or a handgun stable. In fact, unsupported, a rifle is a lot heavier.

I routinely outshoot rifles at the range with a handgun. Why? Because i can hold a handgun more stable than a lot of people can hold a rifle especially at distances of under a 100 ft.
 

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...I have laid out multiple hand guns. In every case the sight alignment seems close to level. It’s hard to tell with lack of any accurate real measurement...


...I have not tried this with an old revolver....however. I have some single actions with high front blades.

And I presume the multiple handguns are autoloaders, with a barrel inside the slide. This is part of what we're arguing about, because the barrel isn't visible, and therefore hard to judge.
But have a look at that single action with the high front sight...making the barrel angle downward. How is a downward sloping barrel going to make a bullet rise?


And let's keep this congenial, okay? ;)
Moon
 

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The bullet can’t defy gravity. It rises because of the angle of the barrel vs the sights.

Anyone with a single action revolver, knows that the front blades are notoriously too high and they shoot low. I have had to shave mine all down. And that was the idea with those guns. The sights weren’t adjustable and you can’t easily add metal, so you remove it for the user based on the range you wanted to sight the gun in.

For the last time....the bullet inistally goes up because of the angle of the barrel vs the sights. There is nothing magical or different that happens inside a gun barrel other than rotation. That’s it...that’s all the barrel does. Adds spin and velocity.
 

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Ballistic performance is based upon the laws of physics and application by engineering.
Ballistic trajectory that the bullet follows the based upon gravitational acceleration and frictional loss due to atmospheric conditions.
Ballistics applied to a free body (projectile).
Initial free body conditions are established at the instant of clearing the muzzle. Prior to that while in the barrel the bullet is in constrained motion, thus not in the realm of ballistics. Because gravity does not yet have meaningful effect while constrained by the barrel.
The ballistic trajectory subsequent to clearing the muzzle is the initial condition for the vector mechanism formulae.
Regarding any muzzle climb as the bullet transits through the barrel
The bullet velocity vector (speed with direction component) is directly parallel to the bore axis.
The bullet velocity magnitude (speed) accelerates to it's maximum that occurs at the muzzle. Muzzlevelocity provided on the ammunition box, not internal speed.
If constructing a free body diagram of the bullet in the barrel before exiting. With the x y z coordinate system with z being the bore centerline, x being perpendicular vertical y perpendicular horizontal. All forces generated in perpendicular to the z axis (bore axis) are equal and symmetric therefore they cancel out and have no motive force in barrel rise or deflection. Rotation of bullet is around the axis and apply rotation not an x y direction motion to the barrel.
What causes the upward barrel movement?
Reactive force of bullet and combustion gasses force acting on the handgun.
So with a locked breach handgun the rearward forces cause the slide to move and barrel to rise cam or link barrel etc.
 

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Hand gun dynamic.
So the bullet is out before the slide moves.
The handgun free body.
The principle of conservation of momentum is the reason why the handgun responds. Conservation of linear motion and rotation.
The initial system is the handgun and chambered round. Before firing the system is at rest.
At firing energy is released by the chemical reaction. The bullet accelerates to muzzle velocity.
So the moment of the bullet (mv) mass time velocity is transferred to the handgun in the opposite direction. Important factor is the energy from the chemical reaction extensive to the expand the gasses. Rotation momentum cause barrel to rotate opposite of bullet spin.
So the hand gun is forced rearward. Realize that the bullet is out of the barrel the locking breach allows pressure to drop before chamber is open.
Inaccuracies inconsistent follow-up etc is due to handgun design barrel lockup combined with the shooter skill and technique. Shooter skill and technique is the dominant cause of how well someone can shoot.
We discuss the technique the locked wrist thread.
 

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Ballistics applied to a free body (projectile).
Initial free body conditions are established at the instant of clearing the muzzle. Prior to that while in the barrel the bullet is in constrained motion, thus not in the realm of ballistics.
The study of ballistics includes all aspects. What happens in the barrel, outside the barrel and terminal ballistics. It’s all ballistics.
 

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The general name "ballistics" may apply to all aspects of firearm ammo etc. and is used for convenience. The physics use of "ballistics" as in my post refer to bodies under gravitational acceleration.

Semantics regarding the name ballistics does not clarify the fundamental misconception of the bullet behavior in the barrel as posted.

My presentation is correct based upon physics principles. The interested reader can do their own research if so interested.
 

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Okay, guys, Smith 64 with a ruler along the sight line; how would the bullet's path ever meet the sight line?
Moon
 

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And if any of you naysayers have something so antique as a revolver laying around, you can prove it to yourself at home...as I've been asking for some time.
Autos are a lot harder to judge, due to the internal barrel.
It was a real wrestling match getting this picture posted, but I have lots more showing the exact same thing.
Moon
 
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