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Mark D
08-24-2017, 02:07 PM
New member here, but long-time reader of TLG and the forum. This issue may have been addressed before, but I searched and didn't find an answer.

Question, when the pistol is canted (i.e shooting around a barricade), does my POA need to shift?

Note - I prefer not to cant the pistol, but find that it is occasionally necessary. (IDPA matches and a recent vehicle-centric pistol class which involved unconventional shooting positions).

Thanks in advance.

Dave J
08-24-2017, 04:54 PM
It depends on how accurate you need to be. It will matter more on a gun or shot where you'd normally require a 6 o'clock hold vs. a "drive the dot" sight picture. For most IDPA-type engagements, I would not expect it to matter very much at all, unless you're trying to hit a small target area, like might occur if there is partial obscurement from non-threats, hard cover, etc. The best answer would be to go test it out with your own gun.

GLB
08-24-2017, 05:23 PM
The bullet impact will follow the sights. If you rotate them to the right, the impact will be low and right. If you rotate them to the left they will impact low and left. How much will depend on the distance as well as how much cant. Close distance will not show a dramatic change but once you get some distance you will see this effect.

txdpd
08-24-2017, 05:39 PM
The only way to know is to get out there and put some rounds on paper from less conventional positions. If you're POA/POI shifts, you're going to have to decide if it's significant enough to mess with.

RJ
08-24-2017, 06:19 PM
I would be very surprised to hear there was any Impact to POI based on simply rotating the pistol.

If the sights are aligned, and you press straight back, the bullet will impact center of target.

The only time I see any canting is shooting one handed, for example in a USPSA qualifier. I'm pretty much just as inaccurate one handed as two hands, though, even if I cant it slightly.

spinmove_
08-24-2017, 06:58 PM
If sights are aligned, it'll shoot where you're aiming. It might SEEM like your shots are low if you're actually pushing them low-left at a cant.


Sent from mah smertfone using tapathingy

Peally
08-24-2017, 07:01 PM
Assuming it's a single good shot your hit will be fine. Recoil will be angled and if you pull shots a certain direction they will angle as well, but it's not major. With both hands being used having an angled gun isn't the end of the world; with one hand significantly angled it can become a problem though.

I would not adjust POA for anything, rather I'd refine my fundamentals so my shots are actually going where I intend.

GJM
08-24-2017, 07:23 PM
There may be some apples and oranges comparisons going on between the theoretical/actual effect, which shows up at greater distances, and the practical effect at IDPA distances.

http://www.accurateshooter.com/optics/canting-effect-on-point-of-impact/

Backspin
08-24-2017, 07:55 PM
As txdpd said, go out there, shoot, and see for yourself.

I messed with canting the gun one range session at 15 yards. Shooting a G19 and using the top of the front sight as my reference, my sights were POA/POI when held straight up.

With my gun canted at 45 degrees, I had to use the opposite corner of the front sight as my POA. For example, if my gun was canted left, the bullets impacted where the top right corner of the front sight was placed over the target.

For IDPA, I'd say canting likely has a more appreciable effect on recoil control/timing than POI shift.

Mark D
08-24-2017, 08:21 PM
Thanks for the input, everyone. Good info. As suggested, I'll get to the range and test actual POI shift (if any).

Gio
08-24-2017, 08:27 PM
A lot of this depends on what kind of target you're trying to hit. Remember, barrels in almost all pistols and rifles are angled up relative to the ground (not parallel to the ground). This is what causes the bullet to rise up and intersect with your gun's sights at whatever distance you are zeroed. If you turn the gun 90 degrees to the left, now your barrel is tilted to the left. The bullet is also not going to climb at all like this, it will begin falling to the ground as soon as it leaves the barrel. The end result may be that you notice that your impact is low of where your point of aim was. I've seen this as much as 3-4" low at 25 yds when shooting canted around a barricade. For low percentage shots like this or trying to hit the upper A box of a USPSA target, I try to keep the gun as perpendicular as I can.

UNM1136
09-07-2017, 04:17 AM
If you really want to examine the concept, try shooting an AR in asymmetrical positions at different ranges. As mentioned above, the bullet is still affected by gravity when it leaves the barrel, causing it to drop without the mechanical offset of the sights. Since there is a slight mechanical offset in the sights the bullet is also launched toward the front sight. With a battlesight zero (25/200) the bullet may not drop too much, but as it moves from zero to 25 yards it approaches the point of aim from the side the barrel is on, and past 25 yards it will continue in the direction of the front sight. Shooting rollover (or urban) prone and SBU prone at 100 yards are excellent references for this concept.

Intentional canting is more of a specialized circumstances/limited distance type of engagement like clearing hard corners when you can't get distance from the corner, or retention drills, or one handed shooting, or barricade supported, where the difficulty (or novelty) of what you are doing makes pure accuracy harder to achieve.

It is my contention that pistols are more difficult to shoot accurately than rifles, and while the rifle may demonstrate the concept, a person's pistol skills may not be up to a practical comparison. Many shooters can't figure out why when they are holding the gun in two hands, dead nuts vertical that they stringing to the lower left of thier target, and moving to a closer distance where a shooter can shoot a one hole group may not be a distance that allows canting to be an observable variable.

Just my thoughts when I have been too many hours without sleep.

pat

P.E. Kelley
09-07-2017, 04:25 PM
With a handgun and typical handguns distances (and targets) it is a non issue. I shoot class demos with the gun at all angles including
upside down on 8" steels to about 15 yards. Trying to split a playing card??? Then lots of stuff matters!

Mark D
09-11-2017, 12:20 AM
I've been the range at least three times since I originally posted this question, but I kept forgetting to test the POI with a canted pistol. Yesterday I finally did some hands-on research, and as others have predicted, there is no appreciable POI shift at close range (under 10 yds). I simulated learning around an IPDA barricade, and realized my off-balance, leaned-over body position presented much more of a challenge to accuracy than the 45 degree cant of the pistol.

I fully believe a canted firearm can cause a POI shift, but I think it only becomes an issue at longer range, the kind of distances typically reserved for rifles.

Thanks to all who contributed advice and ideas.

Jim Watson
09-11-2017, 09:29 AM
I have seen High Power (rifle) shooters with a considerable cant in the standing position. David Tubb is successful with the stance.
Of course they are shooting at known distances and have determined the appropriate sight settings.

Erick Gelhaus
09-11-2017, 02:14 PM
As UNM1136 alludes to, go out & shoot that issue enough to know for you, your skills, your equipment.

What changes for me is the outcome when I screw up the trigger manipulation. I don't see it panning out the same way as when the pistol is upright.

P30
09-11-2017, 02:43 PM
From the German user manual of the HK P30:

19865

Tiefschuss links = POI is low left
Tiefschuss rechts = POI is low right

www.heckler-koch.com/de/service/bedienungsanleitungen.html (http://www.heckler-koch.com/de/service/bedienungsanleitungen.html)

But I think, at 7 yards the effect is negligible. At 25 yards, it will have a noticeable effect.

Peally
09-11-2017, 02:52 PM
Odd, I can invert a pistol completely and the rounds still go where I want.