MIRAGE `~~~

[5.56×250]

I guess this is more of a hats off comment than a question .
My hat is off to all you LR regulars that can hit on targets , live or metallic , at 500+ yards in high temps .
I first saw the effects of heat on accuracy many years ago while working up loads for a 223 Savage action rifle I built for crow control . This rifle was a real shooter, averaging .25 moa over a span of several months of bench shooting in the back yard . At the time , I was the archery pro at a big mom and pop sporting goods store and decided to borrow the crono to get some velocities on a couple loads I had worked up. I always shot in the morning to mimic temps id likely see once crow season came in.
I had set the crono up and tried to get readings without the two 60 watt bulbs turned on, but reading were spastic , so I turned the lights on.
Initially , grouping was very good and on par with this guns abilities. After the first couple groups , the heat from the lights began to show up in my sight picture . Groupings opened up over an inch and were vertically strung out !
This was at 100 yards . How do you know where the target actually is at long range with the heat mirage ? Everytime I start seeing mirage while target shooting I get completely lost and usually pack it in and wait till the temps drop back down .
Those in here that are accurate through midday lr shooting are next level !

 

[milo-2]

I guess this is more of a hats off comment than a question .
My hat is off to all you LR regulars that can hit on targets , live or metallic , at 500+ yards in high temps .
I first saw the effects of heat on accuracy many years ago while working up loads for a 223 Savage action rifle I built for crow control . This rifle was a real shooter, averaging .25 moa over a span of several months of bench shooting in the back yard . At the time , I was the archery pro at a big mom and pop sporting goods store and decided to borrow the crono to get some velocities on a couple loads I had worked up. I always shot in the morning to mimic temps id likely see once crow season came in.
I had set the crono up and tried to get readings without the two 60 watt bulbs turned on, but reading were spastic , so I turned the lights on.
Initially , grouping was very good and on par with this guns abilities. After the first couple groups , the heat from the lights began to show up in my sight picture . Groupings opened up over an inch and were vertically strung out !
This was at 100 yards . How do you know where the target actually is at long range with the heat mirage ? Everytime I start seeing mirage while target shooting I get completely lost and usually pack it in and wait till the temps drop back down .
Those in here that are accurate through midday lr shooting are next level !

I wouldn't sell yourself short quite yet. There is a big difference between heat mirage out west here and a really high humidity mirage you may be experiencing.
I don't think here in WY you could get enough mirage to skew a 100 yard test if you kept the target in focus.
Shooting a target at distance, focus on the reticle and not the target. There really is no way you can(maybe it is just me) bring both into focus like you can in ideal conditions.

 

[lancetkenyon]

Mirage can be a big help at long range steel, when you are trying to hit MOA sized targets, not so much for shooting tiny little groups. Helps with reading wind tremendously. Here in AZ, mirage is almost a constant. And it can get bad enough to make a 1000+ target all but vanish, even with the best glass.

 

[5.56×250]

I wouldn't sell yourself short quite yet. There is a big difference between heat mirage out west here and a really high humidity mirage you may be experiencing.
I don't think here in WY you could get enough mirage to skew a 100 yard test if you kept the target in focus.
Shooting a target at distance, focus on the reticle and not the target. There really is no way you can(maybe it is just me) bring both into focus like you can in ideal conditions.

I'm in GA, do we do have a fair amount of humidity most days. I can watch my crosshairs float an inch in any direction with a good cheekweld and the rifle fully supported on a hot ga day. I've tried to compensate by trying different holdoffs, but success is very sporadic.

 

[5.56×250]

To complicate things, I prefer windless days to test on. That means the mirage floats everywhere, not in a direction that follows the wind direction at the time.

 

[Beluebow]

Mirage can be your best friend and your worst enemy at times. Image shift can have a huge affect on group size and poi. Load development in heavy mirage can easily lead to false positives/negatives. It can defiantly leave you scratching your head with results that don't repeat.

Learning how to read mirage for wind calls takes time and bullets down range. It's not something you can read about on the interent and become proficient at without lots of practice.

 

[milo-2]

To complicate things, I prefer windless days to test on. That means the mirage floats everywhere, not in a direction that follows the wind direction at the time.

My only suggestion would be, you are not under time when testing, your groups do not have to be fired under a minute. Shoot the condition. Adjust the power on your scope.
I fully get that at some point there may be no return to the standard.
Around here in summer, even now, we can shoot till around 9:30 am, then we get some moisture mirage, in summer it lasts for an hour before just nasty heat mirage sets in and lasts till noon, after that it is just an annoyance till around 6pm.

 

[5.56×250]

My only suggestion would be, you are not under time when testing, your groups do not have to be fired under a minute. Shoot the condition. Adjust the power on your scope.
I fully get that at some point there may be no return to the standard.
Around here in summer, even now, we can shoot till around 9:30 am, then we get some moisture mirage, in summer it lasts for an hour before just nasty heat mirage sets in and lasts till noon, after that it is just an annoyance till around 6pm.

Great advice ! That's my problem, I think. Everytime I sit or lay down to shoot , I strive to be perfect . Seeing the crosshairs floating around puts a variable into my routine that is hard to accept. I never had mirage to deal with when I shot archery tournaments , lol !

 

[BHP9]

I had set the crono up and tried to get readings without the two 60 watt bulbs turned on, but reading were spastic , so I turned the lights on.
Initially , grouping was very good and on par with this guns abilities. After the first couple groups , the heat from the lights began to show up in my sight picture . Groupings opened up over an inch and were vertically strung out !
This was at 100 yards . How do you know where the target actually is at long range with the heat mirage ?

Onre thing you can do is get rid of the incandescent lights and use LED's.

 

[5.56×250]

Onre thing you can do is get rid of the incandescent lights and use LED's.

I dont use that chronograph anymore. I have a unit I bought a couple years ago and don't use light . I just set it up in bright sunlite if I need to check velocities

 

[RockyRandy]

Mirage can be your best friend and your worst enemy at times. Image shift can have a huge affect on group size and poi. Load development in heavy mirage can easily lead to false positives/negatives. It can defiantly leave you scratching your head with results that don't repeat.

Learning how to read mirage for wind calls takes time and bullets down range. It's not something you can read about on the interent and become proficient at without lots of practice.

I couldn't agree more with your comment, I have experienced the same thing here in Idaho. Trying to get a rifle to group in the afternoon will only make you want to pull your hair out. Early morning and late at night works the best for me.

 

[BallisticsGuy]

If the target is getting a lot of mirage then drop your magnification and it'll be less apparent.

Shooting through heavy mirage is always poison. You can't correct for it so you just have to minimize or eliminate it.

/thread

 

[dfanonymous]

a couple tips:

Mirage will appear to distort the target the closer YOU are to the ground. When I hunt, be it archery or rifle, I try to be higher than my game. Try changing your line of sight.

When your steel target is dancing, if you feel inclined to take a shot, most misses are high. So try aiming lower edge of target.

 

[Teri Anne]

I guess this is more of a hats off comment than a question .
My hat is off to all you LR regulars that can hit on targets , live or metallic , at 500+ yards in high temps .
I first saw the effects of heat on accuracy many years ago while working up loads for a 223 Savage action rifle I built for crow control . This rifle was a real shooter, averaging .25 moa over a span of several months of bench shooting in the back yard . At the time , I was the archery pro at a big mom and pop sporting goods store and decided to borrow the crono to get some velocities on a couple loads I had worked up. I always shot in the morning to mimic temps id likely see once crow season came in.
I had set the crono up and tried to get readings without the two 60 watt bulbs turned on, but reading were spastic , so I turned the lights on.
Initially , grouping was very good and on par with this guns abilities. After the first couple groups , the heat from the lights began to show up in my sight picture . Groupings opened up over an inch and were vertically strung out !
This was at 100 yards . How do you know where the target actually is at long range with the heat mirage ? Everytime I start seeing mirage while target shooting I get completely lost and usually pack it in and wait till the temps drop back down .
Those in here that are accurate through midday lr shooting are next level !

After reading your comments I am somewhat flabbergasted, ( Yes an old lady term but since I am an old lady it is acceptable) that you would simply quit shooting when you encounter mirage. Mirage can be and is your friend if you understand what it does for you and how to use it effectively to help with your long range shooting. Mirage is a good way to determine the wind direction and speed across the area you are shooting. It's not unusual to see mirage drifting in different directions as you look down range. What is it telling you? The direction and wind velocity as you look down range. It may change a few times between where you are and where you are looking. It also will cause you to determine that you need to change your elevation settings as it will make the target seem to drift upwards which will cause you to hit low as you try to follow its rise., Take the time to learn to read mirage and your scores will improve proportionately. Don't quit when you see mirage, use it to tighten your groups and scores.