Any truth to having 2 different zeroes at different shooting clubs?

[Mystic Precision]

Thanks Jerry. I suspected it was more to do with atmospherics and shooter not reading the range properly more than anything else.

I suppose the 100 yard zero referenced on that forum was just to show the phenomena

Simple enough to test.

Your range, your set up, you shoot how you want, when you want BUT do this over several days with different weather and light.

Have a patchy cloudy, sunny day, you can prove it in a few minutes

Even at 100yds, your POI will shift in bright sunlight vs cloudy... the amount depends on the optics/sight and accuracy of your rifle.

Just ask experienced target shooters how much elevation they change on a patchy sunlight day.

Jerry

PS and there is that pesky thing called mirage

 

[duncansuds]

Shooting at Milcun over a week, my group of guys would check their 100 yard zero every day before moving on to the longer distances. Everyone's rig was sub 0.5MOA....all experienced but 'non-professional' shooters.
Every day....at the same range..using the same ammunition, the zero would shift by a couple of clicks elevation/windage.....every day....every time.
Not much....but we're talking about multiple variables, each of which can change minimally...but they can all add up to visible change.

Keith and Linda call this slipping the scales. This does a few things for the shooter: confirms a "daily perfect zero", reduces chance of unnoticed equipment failure on the line, makes minor shifts in daily variables accounted for, and gets rid of the "click a day" wander ALL optics can and will have (arguable if it's the shooter or the optic �&#56841 it's an excellent practice and I do it for all target shooting sessions with every rifle. Even a three shot to five shot confirmation at 100 yards will save a lot of hassle at 300+ yard if you have made a mistake or have a eq failure.

 

[Ian Robertson]

Every time you shoot your POI will change a bit. Atmospheric changes can put you off the paper at 900m, about 3 minutes from centre up or down.

 

[caramel]

Some adjustments maybe needed from place to place, at 100 yards those differences will be small... JP.

 

[pierre427]

I never had any mentoring, just learning on the go over the past few years. Setting up the scope properly took me 1-2 years. I'm told that a professional shooter can zero his scope with 2 shots but that's definitely not me

Some of the things I've learned (flame on, shooters):

- Shooting at EOSC vs shooting at the Petawawa range: elevation makes a difference, air density is the difference.
- Mounting a scope - properly - takes blue loctite, a little bit of black electrical tape, and tightening and retightening. Once this is done right, you shouldn't have to do it again. If you don't do this right, you may very well end up chasing your zero around.
- I zero my rifle with many shots over many sessions. On different days, the POI will shift naturally due to lighting, temp, air density and so on. I'm going for an average here, where my first cold bore shot will be damned close to there it should be, on any particular day. I don't want just tight groups, I want the average of that group to be in the bullseye.
- Shoot the same ammo always.
- Find the best load for your rifle. Don't shoot the cheap stuff.
- It's not the rifle, it's you.
- ...except when it's the rifle. But it's more likely the ammo.
- If it's not the ammo, and it's not you. You're wrong, it's you.

 

[SIGP2101]

It is infinite number of variables working together against your consistency.
Even if you change your T-shirt it will reflect on POI. Always shoot matches wearing same clothes you used to practice.
Every range have different lightning conditions/angle, that is why you have to adjust from range to range. Zero in the morning is not same zero in the afternoon. Even more pronounced with iron sights. Gun will always shoot same but your eyes play tricks on you. You marrying highly sensitive optical instrument to not forgiving mechanical device and putting weak human element in between.
Did you drink that coffee before match or not, did you eat more than last time or not at all, how much sugar did you consume prior. Maybe you had that cigarette?
Anything plays big factor, try to be consistent in what you doing and eventually it will yield results.

Setting up the scope properly took me 1-2 years. I'm told that a professional shooter can zero his scope with 2 shots but that's definitely not me

Wrong, it takes only one shot to zero if you do it properly from the rest. Because that is the only one that counts - first shot.

 

[tiriaq]

Shooting at Milcun over a week, my group of guys would check their 100 yard zero every day before moving on to the longer distances. Everyone's rig was sub 0.5MOA....all experienced but 'non-professional' shooters.
Every day....at the same range..using the same ammunition, the zero would shift by a couple of clicks elevation/windage.....every day....every time.
Not much....but we're talking about multiple variables, each of which can change minimally...but they can all add up to visible change.

Many rifles will show a slight shift from one day to the next. Even morning to evening there may be slight changes. And that is with quality equipment. A rifle that shows no shift whatsoever, CCB shots always bang on, is to be treasured.

At long range, as Ian mentioned, the changes can be even more pronounced.

 

[a j cave]

when I was at a black powder shoot, the practice range was very wet and the competition range was sandy and dry. At 100 there was any easy inch different.

 

[Melnibonean]

This is what's great about CGN. All this useful and insightful information.

 

[Dogleg]

My rifles will shoot 1 MOA higher between 300-600 at Nikomas than they do on my home range. Past that it will still be flatter than the chart at the SPRA range but it will also be flatter than calculated at home. I blame most of it on the way the wind comes over the landscape and picks up a vertical component, but haven't completely ruled out bullet riding demons. I do know there is no use in arguing with a target, even if the reasons aren't 100 percent certain.