Leica abc ballistic question

[Cbled]

Hey all,
Not sure if this is the best spot for this question or not. Can any of you experienced shooters explain why my geovid hdb 3000 binos don’t need to measure altitude to compute trajectory? As far as I can tell it measures air temp, barometric pressure and angle compensation. Doesn’t elevation factor in to shooting? Or is elevation only needed when you don’t have an exact temperature and barometric pressure, kinda like when I set up my leupold cds dials?

Sorry for the long winded question, thanks in advance for any insight!

 

[83cj-7]

You pretty much got it figured. Elevation doesn’t matter if the device knows the barometric pressure. You only need to know elevation if you don’t know the barometric pressure. The Leica uses temperature and barometric pressure to figure DA (Density altitude). DA is the ultimate measurement of the environment that affects the drag on your bullet.

 

[gr8fuldoug]

I spoke with our Leica tech rep and he replied:
"Angle and temp are critical to a ballistic correction calculated in MOA, MILs or linear holdover, and 3200s do read and include temp and station pressure when providing ballistic corrections in those formats.

They do not include them when programmed to give EHR (equivalent horizontal range). This is because most folks using EHR are dialing custom turrets which are already cut for the conditions in which the shot is being taken. Correcting for those factors in our EHR solution and correcting for them in the turret would create a double correction which could result in a miss."