How much will Elevation Effect Zero?

[Jrb78usaf]

To all, I am in a predicament and I'm seeking some advice from those more experienced than I am. I recently moved from Ohio to California due to military obligations and finally made it out to the range. After getting settled back into the rifle I noticed I had been shooting consistently high at 100yds. I attributed this to not shooting for almost a month and a half, so shooter error weighed on my mind. I decided to walk away and came back a week later. I was still seeing the same problem in my zero and none of this made sense after checking my dope book. I did remember that I had gone from An elevation of 1350ft to 369ft. So my question is would a drop in elevation effect my zero to the point where I have to drop 4/10 of a mil at 100yd? I find this hard to believe and think maybe my scope was bumped during the move. Any insight would be greatly appreciated. Thanks everyone!

Equipment:
Savage 10FCP-K .308 24" heavy fluted barrel w/ break
HS Precision Stock
SWFA 3-9x scope
EGW 20moa base
Burris XTR rings
Harris Bipod

 

[MSS]

Re: How much will Elevation Effect Zero?

You shooting true yards or Meters? That elevation drop will not effect your 100M POI. How are you determining range? Range finder in Yards? And what BDC do you have?

 

[Jrb78usaf]

Re: How much will Elevation Effect Zero?

I really didnt think that at 100yds it would be that big of an issue. The range I went to says 100 yards but my range finder says 110 which shouldnt make too much difference. The scope is set up in .1 mil incriminates. I'm starting to think it just got thrown off by moving but didn't want to make an elevation adjustment until I was certain that was my issue.

 

[Sterling Shooter]

Re: How much will Elevation Effect Zero?

First, you must understand to hit where aimed, shot after shot, consistency is paramount. You appear to have substituted one or more consistencies for others, perhaps, distance, elevation, and/or temperature. You said you have a data book, so why not look into what's different from one range to another. One thing's for sure, if you're calling your shots right-in-there, yet consistently hitting high, you might want to make a sight adjustment and just move on.

Make your sight adjustment and record conditions in the data book. Every time you go to the range observe conditions and record them. You will see eventually that almost anything can effect your zero, and that zero's are not permanent. They are more like yesteday's news.

 

[MD2Colo]

Re: How much will Elevation Effect Zero?

sounds to me like you bumped it on something, man

You will not see a NOTICEABLE change in POI going from 1300' to 300' at 100yds. Be it won't even matter out to 400.

As long as you're consistent, who cares. re zero and go for it.


Don't overthink the issue... $.02

 

[hiddenmongoose]

Re: How much will Elevation Effect Zero?

If its consistently hitting high by the same amount and its grouping as well as it always did then just re zero it , prob bumped it in the moving process.

 

[Jrb78usaf]

Re: How much will Elevation Effect Zero?

Thanks for the input everyone! Everything points to bumping the scope so as suggested I'm just going to make the adjustment and get over it and see what happens. Thanks again!

 

[ropegun]

Re: How much will Elevation Effect Zero?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Jrb78usaf</div><div class="ubbcode-body">Thanks for the input everyone! Everything points to bumping the scope so as suggested I'm just going to make the adjustment and get over it and see what happens. Thanks again! </div></div>
I also suspect the scope was bumped.

FWIW, my .308 is zeroed at 100 yards with Federal GMM 175 for 5,200' elevation. When I shot at sea level last month my gun's point of impact was only 1/4" lower at 100 yards. I adjusted my scope for the 1/4 MOA difference, however I suspect it wouldn't have been a big deal being slightly off on the 1-2 MOA steel targets we were using -- at least for distances out to 300-ish yards.

 

[Powder_Burns]

Re: How much will Elevation Effect Zero?

Could always zero the turrets and then you would know for sure if the turrets have been moved or not. Or mark em with a wax pen or equivalent. Good idea to scribe or index the marks on your scope ring fasteners too.

 

[BadDudes4Hire]

Re: How much will Elevation Effect Zero?

I agree that you should rezero and move on. However, I will say that in Indiana, where I am, not at all far from OH. the air is as thick as air can get most of the time. I know Cali. is dry, and spent some time in Yuba City area, where I couldnt hardly break a sweat if I tried. Could it be that the humidity is causing this issue, and again, not elevation?

 

[MD2Colo]

Re: How much will Elevation Effect Zero?

Humidity affects bullet drop less than elevation changes.