Zero same at sea level & 7500 feet ?

Larry100

FNG
Joined
Sep 14, 2020
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30
I do all of my rifle shooting at basically sea level where I live. My max distance at our range is 600 that I shoot out to.
I hunted 3rd rifle in CO between 6500-8000 feet 2 weeks ago and shot a bull at 452 yards. I used the DOPE that I verified at sea level and dialed at 7500 feet where I shot my bull, same as I would at sea level.

First day in CO my 2 buddies and I all confirmed our rifles at a local range that was at 6500 feet. There was no shift in point of impact on all 3 rifles. I have a 300 win mag and my buddies had a 300 PRC and a 6.5 PRC. We all shot out to 300 yards at the range in CO ( max distance was 300 yards) and DOPE out to 300 yards was dead nuts for all 3 rifles. I was expecting a 1/2" to 2" shift in our zeroes but was definitely surprised.

Still seems very strange to me that all 3 rifles stayed true.

Can anyone speak on this or have an opinion as to why? From what I have read and researched at 7500 feet of elevation change THEORETICALLY there should have been a zero shift?
 

Formidilosus

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Oct 22, 2014
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8,263
Can anyone speak on this or have an opinion as to why? From what I have read and researched at 7500 feet of elevation change THEORETICALLY there should have been a zero shift?

A 100 yard zero is a 100 yard zero from Death Valley to Mount Everest. Even at 300 yards the difference is small enough that it would take a significant shot group size (10+ rounds) and a very precise rifle to see it.
 
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Larry100

FNG
Joined
Sep 14, 2020
Messages
30
Thanks for the replies.

I did imagine if I pushed it out 600+ yards there would be more of a shift from sea level dope.

I gave up on ballistics calculators after finding weaponized math. But I did run the numbers on a calculator just now and seems out to 500+ yards is where the shift starts to occur.
 
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