- Thread starter Klemm
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I would say it depends on the rifle. I don't know that I've seen my precision rifles change much, but I've sure seen hunting rifles that were zeroed in warm weather be way off when taken to hunt in cold climates. If you're hunting, you may only get one shot. Check your zero when you get there!
If you zero your rifle at 100 yds like you should it generally won’t affect your zero when you move around. As noted it will change in very very small amounts. So small it’s a waste of your time to sweat it. Conform it like you said to be sure something mechanical didn’t change but that’s it.
Your zero will stay the same, your dope will probably change. Different environmental conditions will impact your round. Are those differences big enough to be a concern to you? That depends on how far you are shooting or how small a target you are engaging. A good ballistic program will provide the answer provided you enter quality data.
That being said, if you spend the time, money, etc. to go on a hunt, you should check the zero on location to ensure the rifle is still zeroed due to handling. Input the new environmental conditions into the program, adjust your dope, and confirm.
That being said, if you spend the time, money, etc. to go on a hunt, you should check the zero on location to ensure the rifle is still zeroed due to handling. Input the new environmental conditions into the program, adjust your dope, and confirm.
Drop is a product of flight time. Different altitudes present different air densities, and that affects flight time.
Higher altitude equals less density, equals less flight time, equals less drop; and vice-versa.
Any deviation that is less than or equal to average group size is effectively negligible. If you are shooting at a distance where this is a problem, maybe you're shooting too far, or maybe the ammunition/firearm combination needs refinement. Or the shooter...
I used to do all the above, but then I realized that the types of shooting I do permit sighter shots, so the issue became moot. For me...; YMMV.
Greg
Higher altitude equals less density, equals less flight time, equals less drop; and vice-versa.
Any deviation that is less than or equal to average group size is effectively negligible. If you are shooting at a distance where this is a problem, maybe you're shooting too far, or maybe the ammunition/firearm combination needs refinement. Or the shooter...
I used to do all the above, but then I realized that the types of shooting I do permit sighter shots, so the issue became moot. For me...; YMMV.
Greg
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I live in Oklahoma at 1180 feet and zeroed around 70 degrees on average.
My 300 win mag load shoots 1.25 inches higher at 100 yards when I’m at 10,000 feet and 30 degrees. I have confirmed this on several occasions. Mind you this is my load and obviously different powders/primers/projos will act differently. Now I just zero at home and dial down five clicks.
So yes your zero changes.
My 300 win mag load shoots 1.25 inches higher at 100 yards when I’m at 10,000 feet and 30 degrees. I have confirmed this on several occasions. Mind you this is my load and obviously different powders/primers/projos will act differently. Now I just zero at home and dial down five clicks.
So yes your zero changes.
That’s something else. If anything it would be hitting lower because your bullet is slower but a 1” shift is something else.
I agree that a 100 yard zero makes sense if your scope has exposed turrets. Many hunting scopes do not. In these cases a 100yard zero makes little sense. A 200, 250, or 300 yard makes more sense.
There is no practical difference in poi going from sea level to 5,000’ out to normal ethical hunting distances. Hell on a 6.5 creedmoor for example there is a .1 mil difference in elevation at 500 yards. Not enough to matter. Temperature change would make the most difference I would bet.
I am with everyone else. Shoot that rifle and verify.
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One clarification on mine is that on my elk rifle, I’m actually using a 200 yard zero b/c of my reticle. It’s hitting high 1.25 MOA at 200 yards at high altitude having verified on several occasions; presumably b/c air density is less.
It is not accurate to state that it may be off 1.25 at 100 yards as the air difference has not had enough time to impact flight. But what I do is know that I have my rifle normally zeroed 1.5 inches high at 100, then I drop it five clicks to keep a 200 yard zero before heading to the mountains. Then my high altitude 200 yard zero is dead on. My ballistic tables are set off a 200 yard zero.
Sorry to add to the confusion.
It is not accurate to state that it may be off 1.25 at 100 yards as the air difference has not had enough time to impact flight. But what I do is know that I have my rifle normally zeroed 1.5 inches high at 100, then I drop it five clicks to keep a 200 yard zero before heading to the mountains. Then my high altitude 200 yard zero is dead on. My ballistic tables are set off a 200 yard zero.
Sorry to add to the confusion.
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Well that completely changes the context of your post and my response
You need to use a 100 yd zero and just dial on the 200 yd dope. You aren’t making it easier on yourself doing it with a 200 yd zero
I've zeroed 100 yards here, U.S., and flown overseas several times, on some shitty flights. Worried that the rifle and I would arrive together.
Not once in 10 years of trips has the zero changed at 100 yards, here, there, and back.
Now, my 800 meter adjustment was NOT the same here, as Raton NM, or any of the EU countries. That ballistic calculator is a wonderful tool.
If your mileage varies, get a good Snipershide mechanic to help fix the problem.
Jacob and Lindy were two of the best mechanics I had, ohhh so long ago.
vr
Not once in 10 years of trips has the zero changed at 100 yards, here, there, and back.
Now, my 800 meter adjustment was NOT the same here, as Raton NM, or any of the EU countries. That ballistic calculator is a wonderful tool.
If your mileage varies, get a good Snipershide mechanic to help fix the problem.
Jacob and Lindy were two of the best mechanics I had, ohhh so long ago.
vr
The reason you zero at 100 is because of how little impact environmentals affect the bullet. So when you change variables somewhere drastically, it is not affected hardly at all.
Versus a 200 yard zero, it will be shifted off quite a bit more.
Versus a 200 yard zero, it will be shifted off quite a bit more.
The only reason I could think of for zeroing at 200yd is that some scopes with fixed parallax are arbitrarily adjusted for zero parallax at that distance.
Greg
Greg
With my range at 4500ft above sea level, my typical summer DA is 7500ft to 8000ft.
traveling with a rifle, I do not have to re-zero, however, my dope is certainly different at distance. On average with a 6.5 it's .5 Mils at 800 yards off my CO data.
it starts to change noticeably around 200-300 yards depending on the conditions, with a signification change after 400yards.
We have taken hunters with stuff like the Huskemaw scopes set up for 200 yards and re-zeroed them at 100 and then made sure they are lined up at 300 yards according to the BDC dials. With hunting scopes where the turret is not exposed, it's actually easier to adjust as they still work underneath they just don't have a BDC set up like most hunters are used too.
We zero them at 100, and with even the cheap hunting scopes, you can usually pick up the turret cap that is spring-loaded, reset it to that 0 points at 100 and then when you have an actual dope number you can dial it on. It's the same exact process we use for their other scopes but 99% of hunters are too lazy to bother and DOPE their rifles using the turrets. You don't need to do it as far, most will dial to 500 yards no problem because they tend to shoot flat, but guys just skip a few steps and try to wing it. It's the hunter way, shortcuts.
This year alone we have recent a huge amount of feedback from students who have taken big hunting trips around the world. Most are successfully hitting targets beyond ranges they even expected and getting great results. Why, they are not guessing on the shot, but actually dialing in an adjustment meant for their rifle system. We have already received emails starting a Caribou hit at 781, and some Russia Rams at over 400 yards. We even get Pro hunters and changing how they do business from techniques honed in the 1920s, to modern ways of doing business has resulted in great feedback.
We work hard with the Hunters in our class to get them up to speed so they are successful down the road
This gentleman took a Marco Polo Sheep over 500 yards after this class
Also, it helps to over scope the rifle as the hunting scopes are still stuck in 1978, a Vortex on this rig makes much more sense in terms of turrets and dialing. As well with a Mil based reticle, the holds are the same. Mixing a yardage BDC with MOA is not good, MOA / MOA is a better way of doing it, but Mil / Mil works 100% too if you correctly apply what you learn.
There is no guessing, it's DOPE. What is an 1.5" at 300 yards, could it be 2.5" or 3" ? We hear all the time starting class, I missed a 120 yard shot on an Elk and now they are nailing the same animal at 400 and 500+ yards away.
This young lady and her husband scored last week with a great set of trophies,
The results
Changing something from, "That is how we have always done it" to a more modern approach is not a bad thing and we can point to success.
We zero them at 100, we dope them to distance, we reset the way the turrets are used, and also dope the reticle. It sounds like a lot of work, but we accomplish this in our basic 2 day class, the smiles after, hard to argue with. None of these people are going out and sweating a shot well over 100 yards.
traveling with a rifle, I do not have to re-zero, however, my dope is certainly different at distance. On average with a 6.5 it's .5 Mils at 800 yards off my CO data.
it starts to change noticeably around 200-300 yards depending on the conditions, with a signification change after 400yards.
We have taken hunters with stuff like the Huskemaw scopes set up for 200 yards and re-zeroed them at 100 and then made sure they are lined up at 300 yards according to the BDC dials. With hunting scopes where the turret is not exposed, it's actually easier to adjust as they still work underneath they just don't have a BDC set up like most hunters are used too.
We zero them at 100, and with even the cheap hunting scopes, you can usually pick up the turret cap that is spring-loaded, reset it to that 0 points at 100 and then when you have an actual dope number you can dial it on. It's the same exact process we use for their other scopes but 99% of hunters are too lazy to bother and DOPE their rifles using the turrets. You don't need to do it as far, most will dial to 500 yards no problem because they tend to shoot flat, but guys just skip a few steps and try to wing it. It's the hunter way, shortcuts.
This year alone we have recent a huge amount of feedback from students who have taken big hunting trips around the world. Most are successfully hitting targets beyond ranges they even expected and getting great results. Why, they are not guessing on the shot, but actually dialing in an adjustment meant for their rifle system. We have already received emails starting a Caribou hit at 781, and some Russia Rams at over 400 yards. We even get Pro hunters and changing how they do business from techniques honed in the 1920s, to modern ways of doing business has resulted in great feedback.
We work hard with the Hunters in our class to get them up to speed so they are successful down the road
This gentleman took a Marco Polo Sheep over 500 yards after this class
Also, it helps to over scope the rifle as the hunting scopes are still stuck in 1978, a Vortex on this rig makes much more sense in terms of turrets and dialing. As well with a Mil based reticle, the holds are the same. Mixing a yardage BDC with MOA is not good, MOA / MOA is a better way of doing it, but Mil / Mil works 100% too if you correctly apply what you learn.
There is no guessing, it's DOPE. What is an 1.5" at 300 yards, could it be 2.5" or 3" ? We hear all the time starting class, I missed a 120 yard shot on an Elk and now they are nailing the same animal at 400 and 500+ yards away.
This young lady and her husband scored last week with a great set of trophies,
The results
Changing something from, "That is how we have always done it" to a more modern approach is not a bad thing and we can point to success.
We zero them at 100, we dope them to distance, we reset the way the turrets are used, and also dope the reticle. It sounds like a lot of work, but we accomplish this in our basic 2 day class, the smiles after, hard to argue with. None of these people are going out and sweating a shot well over 100 yards.
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Many of my buddies are hunters only. Many of them extremely experienced and successful hunters. Lots of 200yd zeros. I don’t say anything as they aren’t trying to inform or teach anyone. I only take issue on here because there’s a lot of misinformation or out dated info that gets passed along as fact and there are a lot of newer shooters here.
But, 10/10 times when they are calling zero’ing corrections for each other, even at 100 yds and they are using inches, they are never in the ballpark. It’s always 1.5” or 2”.......and when I use my reticle, it’s never over .3
And that’s at 100. At 500+, it’s always way off.
But, 10/10 times when they are calling zero’ing corrections for each other, even at 100 yds and they are using inches, they are never in the ballpark. It’s always 1.5” or 2”.......and when I use my reticle, it’s never over .3
And that’s at 100. At 500+, it’s always way off.
I’m convinced!! This is a great discussion. Thank you very much DT and Lowlight.
I now see my logic was antiquated with the 200 yard zero. I was using a 200 yard zero b/c until recently all my hunting scopes were old school leupold Vx3 with no knobs with varmint reticles. Having to adjust a 200 yard zero with 8,000 to 9,000 feet of altitude changes was creating this situation where my zero was having a significant change. I still figured it out through trial and error how to configure my 200 yard zero in the mountains but this was an exercise in over complicating the issue.
Much easier to just use the 100 yard zero with minimal deviation then use the StrelokPro or JBM to give me me my new holds at altitude. D’oh!!! (Homer Simpson head slap).
I now see my logic was antiquated with the 200 yard zero. I was using a 200 yard zero b/c until recently all my hunting scopes were old school leupold Vx3 with no knobs with varmint reticles. Having to adjust a 200 yard zero with 8,000 to 9,000 feet of altitude changes was creating this situation where my zero was having a significant change. I still figured it out through trial and error how to configure my 200 yard zero in the mountains but this was an exercise in over complicating the issue.
Much easier to just use the 100 yard zero with minimal deviation then use the StrelokPro or JBM to give me me my new holds at altitude. D’oh!!! (Homer Simpson head slap).
So small you’ll usually not even notice. Just check it and run with it
traveling long distances with a rifle concerns me more than the elevation change,
Mine changed. I brought rifles to CO that were zeroed in FL at about 30 feet ASL. At 6.5k ASL I had a different POI
Your gun was zero'ed @ 100y in Florida, verified distance, and it shifted poi at the exact same verified distance?
I suppose there could be perhaps a 1 yard difference between the two ranges.
If you feel differently I’m all ears to your explanation.
How much difference?
If your rifle is zero'ed at 100y on a verified range, measured or lasered in FL, and in CO the same measured and lasered 100y. Then I would ask is it the same shooting position, same mirage (shimmer) the experts have shown the ballistics don't change. Change from prone to bench, vice versa, technique change due to training?
If your rifle is zero'ed at 100y on a verified range, measured or lasered in FL, and in CO the same measured and lasered 100y. Then I would ask is it the same shooting position, same mirage (shimmer) the experts have shown the ballistics don't change. Change from prone to bench, vice versa, technique change due to training?
It was only an inch off, slightly right and slightly lower. While the things you mentioned certainly apply, I’d be very surprised if going from 100% humidity/30 for ASL to almost none/6.5k ASL didn’t effect something.
I’ll mess with JBM when I have more time and run the numbers for both areas atmospheres.
Cool, I thought someone ran the numbers and said it was negligible, or maybe frank talked about it on the podcast.
It' s time,
The conditions don't have TIME to effect a 100 yard zero. I live in CO and travel just about every other week to other locations and I don't have to re-zero elevation,
You need TIME for the atmospheric changes to have an effect and at 100 yards there is no enough time to cause that issue.
My dope at distance is different, but my zero is not.
Humidity has ZERO effect on this, in fact, 100% humidity is better at 1000 yards the difference between 100% humidity and 0% is barely 4/10th of an inch. That is not 4/10th times 10, it's just 4/10th, so how are you are seeing it at 100?
Here is the clue, you have no clue and are guessing, "I would be surprised" ... telling
The conditions don't have TIME to effect a 100 yard zero. I live in CO and travel just about every other week to other locations and I don't have to re-zero elevation,
You need TIME for the atmospheric changes to have an effect and at 100 yards there is no enough time to cause that issue.
My dope at distance is different, but my zero is not.
Humidity has ZERO effect on this, in fact, 100% humidity is better at 1000 yards the difference between 100% humidity and 0% is barely 4/10th of an inch. That is not 4/10th times 10, it's just 4/10th, so how are you are seeing it at 100?
Here is the clue, you have no clue and are guessing, "I would be surprised" ... telling
Chew on this if you want to visualize your dope and the what changes in location have,
look at 200-yard data for not only multiple calibers but multiple locations, compared your 200-yard dope with your 800-yard dope and see how it changes, that tells a big part of the tale
Both 200 and 300 are the same
look at 200-yard data for not only multiple calibers but multiple locations, compared your 200-yard dope with your 800-yard dope and see how it changes, that tells a big part of the tale
Both 200 and 300 are the same
It was either you or the rifle.
Especially when you’re also different with windage. Wind has to be kicking petty hard to throw zero off.
Run calculator numbers with any zero except 100. Then look at dope for 100. Now change all the environmental factors you want in the calculator.
100yd dope won’t change. You can change the DA (which takes it all into account) from 0 to 20,000 and it won’t change.
A lot of new shooters have wandering zeros because they change how they do things every time
In classes, we zero at least 3x, and some guys are solid, others have to adjust, it's quite common, and no traveling involved.
We see scopes not return to zero correctly, we see guys adjust their methods of shooting, we see people change ammo mid-way through and wonder why it's off. It's not uncommon to see a new shooter show up with two different types of ammo and wonder what is wrong with switching from 143ELDX to 129 Superformance, you mean it's different?
In classes, we zero at least 3x, and some guys are solid, others have to adjust, it's quite common, and no traveling involved.
We see scopes not return to zero correctly, we see guys adjust their methods of shooting, we see people change ammo mid-way through and wonder why it's off. It's not uncommon to see a new shooter show up with two different types of ammo and wonder what is wrong with switching from 143ELDX to 129 Superformance, you mean it's different?
However this isn’t always possible. In a hunting or tactical scenario, you don’t have this option.
The point of the thread though is asking about zero change due to location/environmental. In which case, the answer is no, it doesn’t affect zero.
If the zero changes from the last time you shot the rifle, it’s either the shooter or something mechanical. Either way, it should be addressed as such and not written off as location/environment.
I agree but I am not OAF and neither is the OP so my remark pertains to that part of the community. It is foolish not to check your zero for the reasons you state. Transportation shock can radically f up the situation. That was my point
Again, zero to do with the topic at hand.
(Also, didn’t know it’s OAF to be on a hunting trip for a couple days or more and not checking your zero before you take a shot)
You need to buy another scope to occupy your time...maybe a reading comprehension course would help as well as the OP asked about peace of mind in case the scope got bumped in the last sentence of his post.
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1/2 that students that show up to class don't even have their turrets reset to 0 - 0 and wouldn't know what an actual zero is prior.
They don't have the first clue where their zero is, or even how to slip the scales on their turrets. 80% don't even carry the right Allen key to adjust it. In fact, so much so, my fundamental eval sheet has a section for Turrets, because they either have dope left on and miss the paper completely or have a random number as their zero with a very little clue where it is.
Rarely do people who participate in my fundamental eval have what I would call a zero.
The excuse of, they shifted in the case, or some other reason is lame. It's 2019, we have better equipment for the most part, so the excuses just fall short in practice.
If you listen to the last podcast I did with Caylen, when he teaches LE he gives them 15 shots to establish a 100 yards zero. That what it has come too, hoping the guy who works with a precision rifle can zero it in less than a box. Meanwhile, the rest of the shooting community who doesn't handle a rifle for a living is lucky to know how to zero at all.
25 yards, 50 yards, etc, read some of the lame comments about zeroes online and a picture comes into focus pretty fast.
They don't have the first clue where their zero is, or even how to slip the scales on their turrets. 80% don't even carry the right Allen key to adjust it. In fact, so much so, my fundamental eval sheet has a section for Turrets, because they either have dope left on and miss the paper completely or have a random number as their zero with a very little clue where it is.
Rarely do people who participate in my fundamental eval have what I would call a zero.
The excuse of, they shifted in the case, or some other reason is lame. It's 2019, we have better equipment for the most part, so the excuses just fall short in practice.
If you listen to the last podcast I did with Caylen, when he teaches LE he gives them 15 shots to establish a 100 yards zero. That what it has come too, hoping the guy who works with a precision rifle can zero it in less than a box. Meanwhile, the rest of the shooting community who doesn't handle a rifle for a living is lucky to know how to zero at all.
25 yards, 50 yards, etc, read some of the lame comments about zeroes online and a picture comes into focus pretty fast.
Seriously ? 15 ?........
Jeebuz......
Most ranges around here will kick you off the range if you can't at least get on paper in 3 to 5 rounds (@ 100 yds).
getting on paper is not a zero
I appreciate the info Frank. At the same time, this is a forum and I’m sharing my experience without any claim that’s its fact or written in stone.... just what I’ve experienced.
I’m here to learn and I think I’ve pretty regularly shown that I’m more a sponge than a rock.
Over the years, we have seen hunting rifles change zero with wood stocks.
Hunting rifle in climate controlled safe at one moisture content, goes to range, at another, travels in yet another, to hunt in yet another. An unsealed wood stock is more likely to change than not.
Wayyyy.... back in the day, when the m21 was in wood stocks, rifles bedded at Ft. McClellan in Anniston Al, that had been armory stored awhile, went to Panama to the jungle school.
The armorer, Mr. Mac checked them out b4 they left. All was well. Disassembled them, no problem.
After day 3 at the school, the rifles zero wouldn't hold. The unit armorer, not Mr. Mac, disassembled them, the bedding came out attached to the action.
Moisture content in the wood stocks from two changed environments caused that.
Old African hunting stories were told with frequency of stock moisture changing causing zero shifts.
Fast forward to today, with composite or fiber stocks properly bedded. Whether hunting rifle or serious rifle. Lots of people check zero off their favorite location in tee shirt, then travel to 6000' feet and shoot in serious warm hunting clothes that change the rifle's reaction to the shooter. This is a rifle and scope fitted to a condition with the shooter and when conditions change, clothes, positioning, shooting platform changes, well, recoil management changes, and poi may change just enough to cause questions.
We see this often enough to recognize it may happen.
In my case, once upon a time, a Winchester 70, browning BOSS system, a substandard barrel, and really temperate sensitive ammo, and a 60 degree temperature shift caused a major poi shift.
Experiments over the next year determined the shit barrel and nit picking finicky pos BOSS were the issue.
If a shift happens, generally the reason can be determined. Majority of the time, it's the shooter in a new discomfort zone.
That I see every year in the hunting club.
Hunting rifle in climate controlled safe at one moisture content, goes to range, at another, travels in yet another, to hunt in yet another. An unsealed wood stock is more likely to change than not.
Wayyyy.... back in the day, when the m21 was in wood stocks, rifles bedded at Ft. McClellan in Anniston Al, that had been armory stored awhile, went to Panama to the jungle school.
The armorer, Mr. Mac checked them out b4 they left. All was well. Disassembled them, no problem.
After day 3 at the school, the rifles zero wouldn't hold. The unit armorer, not Mr. Mac, disassembled them, the bedding came out attached to the action.
Moisture content in the wood stocks from two changed environments caused that.
Old African hunting stories were told with frequency of stock moisture changing causing zero shifts.
Fast forward to today, with composite or fiber stocks properly bedded. Whether hunting rifle or serious rifle. Lots of people check zero off their favorite location in tee shirt, then travel to 6000' feet and shoot in serious warm hunting clothes that change the rifle's reaction to the shooter. This is a rifle and scope fitted to a condition with the shooter and when conditions change, clothes, positioning, shooting platform changes, well, recoil management changes, and poi may change just enough to cause questions.
We see this often enough to recognize it may happen.
In my case, once upon a time, a Winchester 70, browning BOSS system, a substandard barrel, and really temperate sensitive ammo, and a 60 degree temperature shift caused a major poi shift.
Experiments over the next year determined the shit barrel and nit picking finicky pos BOSS were the issue.
If a shift happens, generally the reason can be determined. Majority of the time, it's the shooter in a new discomfort zone.
That I see every year in the hunting club.
