Elevation and Ballistics

[BrianKY]

I had a small change of plans and I am now hunting the rifle season from October 17 to 25 instead of archery. In Kentucky I am at an elevation of about 450. My question is how much will going to 10000 feet affect my rifle? If I have it sighted in at 200 yards, will it cause it to shoot high?

[Fridaythe13th]

Little bit, not much to worry about at 200 yards. it more of a steep shots up hill or down hill at longer ranges.

[Charina]

There are plenty of ballistic calculation websites out there. Input your info, and change elevation/temp and see how much it changes. I'll second Friday's comment that slopes are a bigger deal to consider than temp and elevation. Aim low whether shooting up or down hill. Again, run the scenarios in the ballistic calculators and see how much of a difference there is. Here is a good article about shooting at angles that provides some good rules of thumb. http://www.millettsights.com/downloads/shootinguphillanddownhill.pdf I keep a cheat sheet of those rules of thumb (as well as elevation and windage compensation for my load) as a background screen on one of the pages on my phone, and a small paper copy with me.

[82ndreddevil]

I used these as a simple rule of thumb when it came to compensating for the environment. Each of these factors would effect your POI by 1 MOA. For example, if I zero my rifle at 5,000 ft and its 70 degrees with no humidity in NM this would be a zero of 225 yards and about a 40" drop at 500 yards. Then I went to 8000 ft with a temp of 50 degrees. In "theory" at 500 yards the temp difference would cause the strike of the round to be Around 45" due to cold temps make the atmosphere thicker (more resistance). But then the increase of elevation creates a thinner atmosphere too. This would cause a round to not drop at the same rate as previous area. In the end, POA and POI is very close In both sceneries.
i just threw out this elev and temp stuff cause you were asking about it plus I think it's interesting. But don't waste your hunt thinking about elevations and stuff like that. These factors I mentioned won't be noticed from a sporter rifle with factory ammo. Definitely pay attention to angles, though I doubt you'll encounter such angles when hunting elk. I'd be more concerned if it were mountain goats or bighorn sheep.

Each of these factors effect POI by 1 MOA

- 20% gain or loss of humidity
- 20 degree gain or loss in temp
- 2000 ft gain or loss in elev.

[Elkduds]

As usual, I will mention that the force of gravity decreases as elevation increases











But not much

[7saum]

I had a small change of plans and I am now hunting the rifle season from October 17 to 25 instead of archery. In Kentucky I am at an elevation of about 450. My question is how much will going to 10000 feet affect my rifle? If I have it sighted in at 200 yards, will it cause it to shoot high?

here's an example on how the POI (point of impact) can change downrange with those extreme changes in altitude. It's unknown how the change can effect your zero at 200 yards, so let's assume you're still hitting dead on at 10,000'

300 Win Mag 180gr Accubond @ 3000 fps

450'
200y 0" zero
300y -6.3"
400y -18.4"
500y -37.2"

10,000'
200y 0" zero
300y -5.9"
400y -17"
500y -33.8"

[Ghost]

Ive gone through that gyration, at the ranges I shoot at, it doesnt matter enough to make any correction.

[powderfinger]

>>>> I don't fuss w/ the change. Practice a lot from field positions out to the longest distance you shoot. You need to know how YOUR rifle and load will drop at the longer ranges. Many times it's not what the ballistic program predicts! My standard is 2 moa from my harris bi-pod.

[Lefty]

>>>> I don't fuss w/ the change. Practice a lot from field positions out to the longest distance you shoot. You need to know how YOUR rifle and load will drop at the longer ranges. ,............

What he said
One thing I always tried to do was test loads and sight in on cool days. I expected a bit of advantage above 9000( coming from 4500) Knowing your exact distance and figure for angle will generally be more important under 400 yards