Same handgun, different POI for two shooters?

[uechibear]

... See for example, the iconic Glock shooter whose pistol is "zeroed" with the rear sight pushed all the way to the right...

Are you referring to an actual person here. If so, who please?

[Surf]

IME, some people don't achieve "equal light, equal height" when they are "reading their sights". I believe that some people may influence the sights with the dot relationship to the notch which may vary from truly flat across the top. So two shooters may get different results with elevation. For windage, I also believe that some people subconsciously "read their sights" with a bias for more or less gap to one side of their sights or the other and do not truly present and fire with equal spacing.

However I believe that far more shooters place a different influence on the weapon when shooting slow bullseye or up close for speed via the grip or how they run the trigger.

[SLG]

Does that include precision rifles?

100%

If it is zero'd, it is zero'd. How the shooter applies force to the gun (and parallax correction, if done wrong) affects where the bullet goes, and that is what accounts for different shooters having different POI. This assumes everything else is correct. If a novice addresses the gun, they likely will not be doing things even close to the expert who zero'd it.

[GRV]

100%

If it is zero'd, it is zero'd. How the shooter applies force to the gun (and parallax correction, if done wrong) affects where the bullet goes, and that is what accounts for different shooters having different POI. This assumes everything else is correct. If a novice addresses the gun, they likely will not be doing things even close to the expert who zero'd it.

Thanks, this is very helpful.

In practice, for a skilled, squared-away team, if you took two snipers that were issued and used identical equipment, could you swap their guns at zero hour and trust either of them to make a hostage rescue shot at a typical distance (I have no idea what that even is) without re-zeroing the new rifle? For argument's sake, assume both rifles are warm and fouled, and assume you could trust each sniper to make the shot with their own rifle.


I've always conceptualized the "zero" as an objective, mechanical, human-independent thing, which is what I think you're saying. However, I've butted heads with some people about this before, so I'm curious to understand it better.

Do you feel that all duty guns should be ideally zeroed in the absolute sense of the term that you've suggested, or do you think they should be adjusted to accommodate for the sort of shooter--gun interface you're referring to? If the latter, where do you draw the line between shooter--gun interface vs. consistent technique problem?

[P.E. Kelley]

IME, some people don't achieve "equal light, equal height" when they are "reading their sights". I believe that some people may influence the sights with the dot relationship to the notch which may vary from truly flat across the top. So two shooters may get different results with elevation. For windage, I also believe that some people subconsciously "read their sights" with a bias for more or less gap to one side of their sights or the other and do not truly present and fire with equal spacing.

However I believe that far more shooters place a different influence on the weapon when shooting slow bullseye or up close for speed via the grip or how they run the trigger.

I absolutely do.

[ASH556]

Are you referring to an actual person here. If so, who please?

I would guess he's talking about Bob Vogel. If you grip a Glock like he does, the massive triggerguard acts as a torque lever when applying pressure with your support hand and pulls the gun left, hence, drifting the rear sight to the right. That grip does allow you to keep the gun damn flat, though. I don't notice any windage drift when using that aggressive grip and shooting for speed inside 10 yds. Once you move beyond that, though, the sight drift becomes necessary (in my experience anyway).

[GRV]

Are you referring to an actual person here. If so, who please?

Sorry, my posts never seem to read the way I mean them.

No. I was just referring to the stereotype. Right-handed Glock shooters tend to shoot left, and there's a trend of misinterpreting this as a zeroing problem and compensating for it by drifting the rear sight. So, the notion of inexperienced Glock shooters having their rear sights drifted all the way to the right edge of the slide is one I'm familiar with and don't want to fulfill, personally.

But the question is, if you're consistent enough about it, does it ever at some point cease to matter that it's Wrong? Say you can clean Dot Torture at 10 yards on demand, consistently, but only if you drift the sight to the right a little, maybe that's okay even if it makes the gun objectively speaking "not zeroed"?

I tend to take the side of trying to make my guns objectively, ideally, mechanically zeroed and then viewing any sort of consistent offset in my groups as a technique problem that I need to solve. But, I realize there other people that find it silly to think of the zero in such a cold theoretical way, and instead emphasize the notion of the shooter--gun interface more and align the sights to accommodate for that at some point.

I'm trying to better understand this spectrum and where the various truths lie in this topic.

[P.E. Kelley]

Sorry, my posts never seem to read the way I mean them.

No. I was just referring to the stereotype. Right-handed Glock shooters tend to shoot left, and there's a trend of misinterpreting this as a zeroing problem and compensating for it by drifting the rear sight. So, the notion of inexperienced Glock shooters having their rear sights drifted all the way to the right edge of the slide is one I'm familiar with and don't want to fulfill, personally.

But the question is, if you're consistent enough about it, does it ever at some point cease to matter that it's Wrong? Say you can clean Dot Torture at 10 yards on demand, consistently, but only if you drift the sight to the right a little, maybe that's okay even if it makes the gun objectively speaking "not zeroed"?

I tend to take the side of trying to make my guns objectively, ideally, mechanically zeroed and then viewing any sort of consistent offset in my groups as a technique problem that I need to solve. But, I realize there other people that find it silly to think of the zero in such a cold theoretical way, and instead emphasize the notion of the shooter--gun interface more and align the sights to accommodate for that at some point.

I'm trying to better understand this spectrum and where the various truths lie in this topic.

Damn Dude that's deep thinking.

I zero for me. Where that zero leaves the sights is of little importance.
Now with that said, I can't stand sights not being centered in their respective moorings!
I have yet to own or shoot a Glock that did not zero with the sights centered.
I have a few handguns that if it were not for their enviable accuracy, would be gone due to the sights needing to be
adjusted off center to produce shots to the POA.

Ultimately I rarely miss at speed due to sights issues. I, like I bet most of us, miss align our sights...during the last execution of the firing process.

[GRV]

I think I mangled the point again. I hate the internet... I hate words.

To be clear, when I say "objective, mechanical zero", I don't mean perfectly centered. How the sights end up geometrically is irrelevant. I just mean whatever mechanically aligns the sights with the POI, so that it'd be zeroed for a ransom rest or a perfect android shooter.

If I try to explain what I'm wondering about here any more precisely, it's going to go far past the "give a crap" word limit for anyone here. I know because I just deleted exactly such a rant. I think the questions I asked in #24 are the most likely to help me learn what I'm curious about here, and so let's just imagine I never opened my mouth after that

[SLG]

Thanks, this is very helpful.

In practice, for a skilled, squared-away team, if you took two snipers that were issued and used identical equipment, could you swap their guns at zero hour and trust either of them to make a hostage rescue shot at a typical distance (I have no idea what that even is) without re-zeroing the new rifle? For argument's sake, assume both rifles are warm and fouled, and assume you could trust each sniper to make the shot with their own rifle.


I've always conceptualized the "zero" as an objective, mechanical, human-independent thing, which is what I think you're saying. However, I've butted heads with some people about this before, so I'm curious to understand it better.

Do you feel that all duty guns should be ideally zeroed in the absolute sense of the term that you've suggested, or do you think they should be adjusted to accommodate for the sort of shooter--gun interface you're referring to? If the latter, where do you draw the line between shooter--gun interface vs. consistent technique problem?

I don't know.

I have swapped guns with many of my teammates over the years and found that we had the same zero. It's easy ot figure that part out. As for "what a zero really is", I don't know, and I don't know that it matters. Whether mechanical or as a compensation for some physical "limitation" (for lack of a better word), it doesn't really matter. All that matters is that it hits where you want it to hit.

Given 2 or 100 shooters, in the prime of their life, with excellent fundamentals, and high quality equipment, I have found that a "zero" is a zero, regardless of the individual.

That can and will change from group to group.

Anecdote that I don't know as much about as I would like: During Vietnam, snipers and spotters would share one sniper rifle, in order to give the sniper a rest from looking though the scope. Whether it was ever a problem or not, IDK. Guns were also less precise then, so again, IDK.