rifle shooting through angled ports....how does one accommodate for cant?

[mtenenhaus]

I try very hard to make sure i'm not canting the rifle (or any firearm), especially when shooting longer distances.

I've noticed that in some competition formats, competitors must shoot through angled ports. I was wondering how one accommodates for the effects of cant on trajectory with any measure of precision.

I appreciate that in general when shooting an an angle the distance calculated is short due to the effects of gravity....and i've a bit of a recollection of the value of cosine factored calculations.......however, i can't imagine a competitor is doing that kind of math in competition. I also can't imagine that people are just winging it as this position is quite common.

Appreciate your help/experience.

[sonofeugene]

I don't see it to be much different from regular sights except that you need to compensate for the distance your canted sights are off the vertical center of the rifle bore in the sight picture. This applies if the rifle remains in its normal shooting orientation.

If the rifle is rotated about the bore axis so that the canted sights are now at the 12 o'clock position, the sights work as normal.

[HKAllTheThings]

You hold in the direction of the magwell. So, if the rifle is rolled 90 degrees right, you hold left.

[OCEquestrian]

You hold in the direction of the magwell. So, if the rifle is rolled 90 degrees right, you hold left.

You still have to hold higher. The bullet begins dropping as soon as it leaves the muzzle...straight down...always.

[HKAllTheThings]

You still have to hold higher. The bullet begins dropping as soon as it leaves the muzzle...straight down...always.

Bullets aren't dropping when they come out of the muzzle.

[hermosabeach]

Practice and log book.

Some shoot prone at a cant. They know their load and their sights and are consistent with positions. They know how to adjust for not being 100% level.

[hermosabeach]

I was watching guys shooting 8” groups @600 from prone with iron sights

They were in their shooting jackets and were off axis.

I asked about being on their side.... they log every shot and learn how to adjust for prone vs standing with impact.

[mtenenhaus]

thank you
it's a fascinating sport

[sonofeugene]

Bullets aren't dropping when they come out of the muzzle.

Actually, the bullets do drop when coming out the bore. Look at your bore axis vs the bullet trajectory. What one has to do to hit a target at a certain distance is to aim high so that the bullet can hit and not be too low.

[OCEquestrian]

Bullets aren't dropping when they come out of the muzzle.

The law of gravity affects the bullet as soon as it leaves the barrel. In fact if you shoot a bullet straight out of a gun, totally parallel to the ground and you drop the same weight/type of bullet from a height the same as the center axis of the bore of the rifle you are using for the shot, both the shot bullet and the bullet you drop will hit the ground at the exact same time.

GO BACK TO PHYSICS CLASS!

[sbo80]

It might be semantics, but words matter. The point of the graphic is that the way sights are aligned on a rifle, you don't fire "totally parallel to the ground". That example is not relevant. The gun is angled upward. The bullet does not "start dropping right away". Being fired upward, gravity starts reducing the upward travel, but upward it still is, until it reaches the apogee of the arc. On a 50yd zero AR15, that occurs past about 100 yards. So the bullet does not in fact "start dropping" until that point. That's basic physics class stuff.

[smoothy8500]

You hold in the direction of the magwell. So, if the rifle is rolled 90 degrees right, you hold left.

All the pointless arguments about bullets rising/dropping haven't answered the OP's question except this one. Regardless of "when" or "where" bullets drop, the sights are regulated for gravity in an upright configuration. Take those drawings and place them sideways to understand @HKAlltheThings explanation.

[Gun Kraft]

I've noticed that in some competition formats, competitors must shoot through angled ports. I was wondering how one accommodates for the effects of cant on trajectory with any measure of precision.

What distances are you referring to? Usually those competitions involve shooting targets through angled ports that are within 100 yards. At that point POA/POI deviation is within an inch or two so there isn't much math involved.

[HKAllTheThings]

Sorry for any confusion. The mag well thing is something simple to remember and you need simple things when things outside you get complex.

[sonofeugene]

It might be semantics, but words matter. The point of the graphic is that the way sights are aligned on a rifle, you don't fire "totally parallel to the ground". That example is not relevant. The gun is angled upward. The bullet does not "start dropping right away". Being fired upward, gravity starts reducing the upward travel, but upward it still is, until it reaches the apogee of the arc. On a 50yd zero AR15, that occurs past about 100 yards. So the bullet does not in fact "start dropping" until that point. That's basic physics class stuff.

Actually, the bullet does start dropping immediately upon leaving the barrel. To do otherwise would defy the laws of physics. And it drops in a linear rate relative to the bore axis it was fired from.

But relative to the ground, it does continue upwards but at a reduced rate because, again, of gravity.

We may be talking the same points here. Simply put, no matter what direction the barrel is pointed in, gravity will always affect its trajectory and starts doing so as soon as the bullet leaves the barrel.