[Lautermilch]

The 36 Yard Zero

The 36 Yard Zero Target In the recent carbine courses we have discussed various yard lines to zero your rifles along with the pros and cons of each yard line. For those that have attended the courses now know that when it comes to your go-to 5.56 caliber carbine rifle that you would pick...

www.vigilanceelite.com

 

[bttbbob]

The 36 Yard Zero

The 36 Yard Zero Target In the recent carbine courses we have discussed various yard lines to zero your rifles along with the pros and cons of each yard line. For those that have attended the courses now know that when it comes to your go-to 5.56 caliber carbine rifle that you would pick...

www.vigilanceelite.com

Good article and helpful but there is a glaring mistake.

The bullet is still rising to meet your point of aim at 36 yards, this is why the impact point is low on the target.

Bullets never rise, that would be defying gravity.
They are aimed higher.

 

[Riverpigusmc]

Good article and helpful but there is a glaring mistake.

The bullet is still rising to meet your point of aim at 36 yards, this is why the impact point is low on the target.

Bullets never rise, that would be defying gravity.
They are aimed higher.

Yep.Amazing how many people believe bullets arc after leaving the barrel.

 

[Lautermilch]

so this chart is incorrect?

 

[brownie]

so this chart is incorrect?

View attachment 75885

Whats the height of the scope over the bore? Without that plugged in, the above chart is useless.

 

[Denverd0n]

The point is that the barrel is ever so slightly angled upwards when you fire the gun. The bullet travels upwards until it reaches its peak and then begins to travel downwards. Regardless, as soon as the bullet leaves the barrel, gravity starts working on it, and starts pulling it downwards. It is only because the barrel is angled upwards to begin with that the bullet is able to travel above the sight line until gravity finally stops that and starts it back downwards.

As such, no, the chart is not necessarily incorrect. My guess, based on the zero distance, is that the chart is based on the sight line being 2.5 inches above the center of the bore. It would be much better if they called that out specifically, though. Of course, the ballistic coefficient of the bullet also has an effect. Without knowing that, the chart is less useful than it could/should be.

 

[Steve48]

The point is that the barrel is ever so slightly angled upwards when you fire the gun. The bullet travels upwards until it reaches its peak and then begins to travel downwards.

Exactly. The bullet does in fact go up, and it does in fact travel in an arc, albeit a shallow one.

 

[Riverpigusmc]

It travels in an arc because the barrel is elevated above horizontal. The bullet itself does not rise above the plane of the barrel, it goes where the barrel is pointed, and starts to fall immediately due to gravity

 

[Steve48]

It travels in an arc because the barrel is elevated above horizontal. The bullet itself does not rise above the plane of the barrel, it goes where the barrel is pointed, and starts to fall immediately due to gravity

Correct. The bullet doesn't rise above the plane of the barrel, but if the barrel is elevated so that the plane of the barrel is not horizontal, then the bullet rises above the plane of the horizontal. That's what most people mean when they say something "rises".

Getting back to the discussion at hand, if the sights are adjusted so that boresight of the gun is elevated with respect to line of sight established by the sights, and you then fire horizontally as established by the sights, then the bullet will rise after leaving the barrel. It will hit lower on a target at very near range than on one at somewhat farther range.

It's been a very long time for me, so maybe you can help me here. If I recall correctly, "battlesight zero" for an M16 at 25 yards was about 3 inches lower than the point of impact at 300 yards.