Effect of mirage at 300 yards?

[nic_reload]

Shooting a bull barrel, 260 rem at 300 yards, almost no wind, -5°c, scope is sightron at 50x, gun shoots regular .3 moa with slow pace shooting.

With a fast pace I was getting a lot of mirage and the 6 or 7th shots were always two inches above the group.

Could the mirage change the POI? Barrel was just warm at the touch...

 

[RifleDude]

You're just finding out what F-class shooters have known for a long time. A lot of them use mirage shields to prevent the problem you've been seeing. Shooting distance has nothing to do with it.

http://bulletin.accurateshooter.com/2013/03/mirage-shields-not-just-for-benchresters-anymore/

 

[frigpig]

Wide venetian blind piece + stick on Velcro tabs = no mirage from barrels.

"Real" mirage is a whole different story.........

 

[nic_reload]

As always, shooting and reloading make you discover new stuff every day!!! Thanks for the answers!

 

[Mr. Jeffery]

even a newspaper/magazine/old folded up target draped over the barrel under the scope and forward of the bell will work in a pinch.

Wide venetian blind piece + stick on Velcro tabs = no mirage from barrels.

"Real" mirage is a whole different story.........

What I stated above is something that Del told me. He also said that the same newspaper rolled into a tube and placed over the bell will aliviate mirage. Not sure I believe this.. regarding real mirage but it works for barrel heat none the less.

 

[J996]

If you are at a range you can aim a small electric fan to blow over top of the barrel.

 

[Brutus]

Turn down that variable scope to something workable under those mirage friendly conditions. (20-25X or thereabouts)

 

[mebiuspower]

If you are at a range you can aim a small electric fan to blow over top of the barrel.

 

[Foxer2373]

Wow and I thought I had too much crap lol this is a new one on me.

 

[Major Sights]

Wow and I thought I had too much crap lol this is a new one on me.

I too was skeptical of that item till a quick google search showed me its actual power.

[youtube]Rgt58sfdo4o[/youtube]

 

[mebiuspower]

 

[Mystic Precision]

If you are at a range you can aim a small electric fan to blow over top of the barrel.

This is what you need when shooting long strings and getting barrel heat caused mirage... NOT the barrel cool. Pretty hard to keep shooting with a fan stuck in the chamber

The barrel cool is useful when you stop shooting and want to cool the steel... problem may be caused by introducing moisture into the bore. This will really depend on the humidity you shoot in. That fan that was blowing air over your barrel can keep on blowing air over your barrel and will do the exact same thing with no risk to next shot flyer.

I prefer to use towel soaked in cold water or nowadays, packed with snow. But I digress.

To the OP, barrel heat related mirage causing VISUAL POI shifts is very well known.... barrel shield or even the lightest breeze over the barrel... DONE.

Jerry

 

[nic_reload]

Thanks to all for answers and suggestions,

I already knew the mirage would cause some visual movement of target in the scope, let's say a one inch movement in every direction. But not that it could translate to a 3 inch change of POI on target ...

I tried the shield trick, worked perfectly! I'll also try the fan...