I sight in and shoot my rifle in nd. the area is around 1300 feet above sea level. I was comfortable shooting out to 400 yards. I went to Wyoming antelope hunting and I think the elevation was around 5000. I shot my antelope at 400 yards and it did not seem to change the point of impact at all. I did shoot at a target out there before I shot at the antelope. but my question is there was no change that I noticed at 400 yards going from 1300 ft to 5000 ft in elevation but would I notice a change in point of impact going from 1300 feet to say 9 or 10,000 ft? I've just seen this topic on long range pursuit and I was curious what other's opinions are.
If you want basic answers, log on to the hornady ballistics calculator and click on advanced options. Enter your load and other variables. This will let you mess with different things like elevation, humidity, temperature, and more. I have noticed that if I sight in at 1000 feet of elevation in 80 degree weather, I will be very close at 8000 feet of elevation at 30 degrees. By changing altitude 7000 feet I would have thought I would hit high but the drop in temperature basically negated the change. I am no expert but have many years of sighting in at low elevation and hunting at high elevation. I try to sight in at home in warm weather... Usually gets you close.
It should be higher at the higher elevation out there, but not enough to worry about, especially with the temperature difference you'll probably be experiencing as mentioned in the other post! Mine are sighted in here in MI at under 1000' and I notice no difference in any of my rifles and we're from 6,500' up to 8,000' feet in Wyoming where I hunt every year.
I just did the calculation for my .270 WSM and basically the bullet will hit 3.6 inches higher at 10,000 feet elevation than it will at sea level (0 feet elevation) at 500-yards. The difference is about 2/10th of an inch higher at 200-yards, less than 1/4 of an inch. I would say for most applications it would be a non-factor. A good exercise though. -G
Good to know Guy! I'll be bringing my .270wsm to Wyoming. And though I've already worked up my load, I will be "tuning" it this summer in 80-90 deg weather. So I should be good. Even so, 3.6 inches at 500 yards is less than what I thought it would be.
Used to shoot lots of 1000 yard matches and we never shot w/o re-sighting before every match. That way any environmental/geographical effects were compensated for.
Thats what i was going to touch on..Dont need to worry about the altitude nearly as much as taking into account any Angle that comes into play if your in the mountain areas. Steeper it is, more you need to account for it. It is something you will want to remember if you get into a quick shooting scenario and forget that you need to take that into account. I personally almost didnt get my sheep in 2007 because i got in a run and shoot type scenario and didnt take in the angle due to not thinking clearly; shot over his back on the first shot, luckily he gave me one last chance before disappearing and I realized what i had forgot and made the correct adjustment and he flopped over and i was very relieved...last day of the season just before dark. I make sure to tell all clients I guide exactly where to aim when we get on animals because the majority come from flat land areas and do not understand the angle compensation.
If you are planning on shooting over 400 yards the difference becomes pretty substantial. I missed an antelope a couple years ago in Wyoming at 830 yards due to not adding elevation into my shooting solution. I am pretty accurate at that range normally and was very surprised when he ran off. It will also effect the wind drift calculation part of the solution.
Turned out I was able to crawl up to 342 yards and kill him. He had a very nice pierced ear from my first shot.
If you are planning on shooting over 400 yards the difference becomes pretty substantial. I missed an antelope a couple years ago in Wyoming at 830 yards due to not adding elevation into my shooting solution. I am pretty accurate at that range normally and was very surprised when he ran off. It will also effect the wind drift calculation part of the solution.
Turned out I was able to crawl up to 342 yards and kill him. He had a very nice pierced ear from my first shot.
I expect it would make quite a difference at that distance. I dont shoot over 400 yds and I try not to shoot over 300 yds so it has never effected my shots enough to worry about.
The elevation angle an wind all have to be accounted for I can dial my rifle 950yd with on turn on the turret here at home 750 feet an at 10,000 feet I gain 100yds on my turret the angle if steep enough will change it as well I ranged a bull on my last hunt with a 19 deg angle turned a 750yd shot into a 700yd shot after the angle was took out of it I did not take the shot because of the wind I was getting a reading on wind meter of 10 to 15 mph were I was setting an looked like more than that between me an the bull but it would die down buy the time I figured out that when the wind was blowing were I was it was laying down between me an the bull he had moved up in the timer theres a lot more to long range shooting than ranging an pulling the trigger
I always make a practice of putting at least a few rounds down range after getting to the hunting location. Unlike most I actually travel from sea level to 10000ft and with 1300 miles and a lot of bad roads, there is a lot of potential for throwing things out of sorts. I guess the bonus is that any compensation for elevation would be adjusted at the same time you check that everything is still zeroed where you want it.
I personally don't shoot further than 400yds so elevation even zero to 10K wouldn't matter but a big pothole might. The other thing I do Prior to heading out is an annual shooting session at a crazy steep angle both up and down. I'm no ballistics guru but I'll bet that a 45 degree shot is going to require a heck of a lot more compensation than elevation.
As far as angle compensation goes, is impact affected the same uphill as it is downhill? Say for instance you have a 300 actual yard shot at a 45 degree angle downhill so you might shoot it like it was say 250 yards, would it be the same if it were a 300 actual yard shot at a 45 degree angle uphill?
I hope this helps. I learned something today. Good question 2nasty4u. It seems like I should have known from archery, but the synapses are not firing on all cylinders. I also don't shoot over 400 yards so the biggest thing (other than angles now) I usually worry about is the wind. I need to make a new card with the angles and wind and distances and everything. What do you guys put on your card for references?
As far as angle compensation goes, is impact affected the same uphill as it is downhill? Say for instance you have a 300 actual yard shot at a 45 degree angle downhill so you might shoot it like it was say 250 yards, would it be the same if it were a 300 actual yard shot at a 45 degree angle uphill?
The short answer to your question is yes. The steeper the angle weather up or down hill, gravity has less affect on the trajectory arch. Basically gravitational pull parallels the earth surface, therefore if you fired a shot perfectly vertical either straight up or straight down there would be no gravitational arch of the projectile.
The short answer to your question is yes. The steeper the angle weather up or down hill, gravity has less affect on the trajectory arch. Basically gravitational pull parallels the earth surface, therefore if you fired a shot perfectly vertical either straight up or straight down there would be no gravitational arch of the projectile.
That's kind of what I was thinking. I used to shoot a lot of 3-D archery tournaments and seemed to remember shooting uphill shots the same as downhill shots. I was talking to a buddy of mine about this topic and he seemed to think that you would have to put more on it for an uphill shot. Like say shooting an uphill target for 30 yards when the actual distance is 20 yards.
This shows the same thing for archery, aim lower for both uphill and downhill angles, steep angles. The chart they had shows that it doesn't make a big difference at low to medium angles. I don't think that you need to put more power behind the shot shooting, uphill. Just the opposite. I guess I am assuming small angles . Gravity works perpendicular to the earth's surface, so by shooting uphill you kindof compensating for the arrow drop, so you will hit high. Same for downhill, the actual horizontal distance to the animal is less than the slant distance measured by the range finder without angle correction, so say you range him at 33 yards, the actual horizontal distance that should be used to measure the arrow drop will be less like 30 yards or whatever the chart says.
http://en.wikipedia.org/wiki/Rifleman's_rule#Inclined_trajectory_analysis. The inclined trajectory picture I think shows it pretty well. This explanation is right up Colorado Cowboy's alley. Please help! http://www.exteriorballistics.com/ebexplained/article1.html. Maybe this one makes more sense. I think for our purposes we will assume that the curvature of the earth is negligible, drag on the bullet is negligible, and gravity is a constant working from the center of the earth, so perpendicular to the surface of the earth.
Say you zero your rifle at a zero angle, completely horizontal. Then you see a deer or porcupine or something up the hill at 30 degrees. You are rotating your line of sight/bullet trajectory chart up to 30 degrees like in the second link or whatever, but gravity will still be working in the same direction, perpendicular to the earth, so perpendicular to your line of sight if you were looking through a leveled transit or something. The slant distance (distance from you to the deer uphill or downhill) will always be longer than the actual horizontal distance, which is the distance over which gravity has its affect on the bullet drop, so you will always hit high if you use the slant distance to range your shot. Feel free to help out, this made sense to me, so it probably made sense to no one else. That is kindof how I roll.