I've been searching the web and forums for information about the effect on a rifle scope's internals based on long days in the hot sun and it's effect on changes in the scope zero. Has anyone done side by side testing of identical scopes mounted on heavy fixed jigs, both zeroed to the same point of aim, fully shading one scope and checking for wandering of the zero based on ambient temp and scope tube temp? I've been at some shoots with incredible wide changes in temperature, add in the scorching direct sunlight to an airtight sealed tube, it seems to me that it would have some impact for the ELR shooters. Any thoughts or known previous tests before I jump into this?
Rifle Scopes Effect on scope zero from changes in ambient temperature (fully shaded) vs. direct sunlight (unshaded)?
- Thread starter ken4570tc in WY
- Start date
I've never had any issues with zero due to heat from the Sun on the scope. Your ammunition will likely suffer differences and velocity long before you have any scope issue as a result of temperature differences between being in the shade and being in direct sunlight(heat). What I have had happened is shifts in point of impact due to lighting conditions.
Somewhere on this site, maybe in the Optics section, somebody did a elapsed time video from Shooters Viewpoint throughout the day. You can sit and watch the target move around.
Somewhere on this site, maybe in the Optics section, somebody did a elapsed time video from Shooters Viewpoint throughout the day. You can sit and watch the target move around.
It is not uncommon to see parallax changes with temperature, not zero. In good quality scopes there is no perceptible zero shift with temperature unless something got through QC that shouldn't have.
ILya
ILya
Fixed mechanical elements won't change. Zero shift with temp changes would be due to ammo changing velocity is what I'd first think of, and then any mirage or parallax shift.
I suggested testing in a heavy fixed jig to avoid ammunition being a factor. However, the air density and humidity changes should register the same with two side-by-side identical scopes with the exception of one scope shaded from direct sunlight.
