Elevation versus arrow flight?

[jmoudy]

From what I understand and have read the higher you go up in elevation the more rise/lift (or whatever it's called) your arrow will fly.

My bow is tuned in at 400ft elevation in the valley where I live but I hunt around 7000ft. I've tuned my bow to shoot roughly 2-3 inches below my target center to compensate for the difference in elevation when I go hunting. I'm shooting Rage mechanical.

How much rise will I get at that elevation versus where I'm tuned in at? I know I just need to take my target with me and shoot it to test but I was wondering with all the wealth of experience on here what experiences others have had on this subject.

Thanks.

 

[OPAH]

Really? first have heard of that, looking forward to the responses. I sight and tune at what ever MO Valley is and hunt any where from 4000 to 7500 feet and have not really seen a major difference in my arrow flight.

 

[Revo2811]

Yep I always take a target and shoot a few times . You might have to raise or Lower your sight a few clicks . Everything else will follow


?

 

[Deleted member 33033]

I haven't seen a difference at 7000', perhaps higher I will but you can easily adjust to whatever miniscule difference that may exist by setting your pin on the target a hair lower.

 

[OPAH]

an inch one way or the other isn't going to screw up my shot, for me its set it and leave it be.
Hate tweaking things in the field.

 

[Orygun]

Practiced and tuned at 3000 feet (my place) hunted as high as 11,500 feet last year. Didn't notice a difference. One thing I would keep in mind is that the higher you go the cooler it will be and you may be wearing more clothing and/or jackets than you did when you tuned at the lower elevations. That can impact your shooting.

 

[jmoudy]

So I took my target out to test the variances in elevation and my arrow impact/flight. I'm tuned in at 400ft and took it to 7500ft. I didn't shoot a ton of arrows but the ones I did shoot all landed higher than they would at 400ft. I would say 2-3 inches higher than normal. I have the same arrows fletched with two different fletchings one with slight helical and one with full helical. They both flew higher than normal by 2-3 inches. I was only shooting at 30 yards. Next time I will try it at the longer distances see if maybe the variances increase. I missed a buck at 60 yards the same day. I'm pretty sure I over shot him (this was before I did the test).

It sounds crazy but I wonder how temperature impacts bow performance/arrow flight. With the limited knowledge I have in science, to my understanding when it's colder some objects can contract while when it's hot some objects expand (all be it minimal). I once had a teacher tell me a story of how when they lay train tracks they have to leave a slight space between them due to when they heat up and expand and one story (I guess way back when maybe? lol) some idiots learned the hard way and didn't leave a space and when it got hot they expanded and the tracks warped out or were bent out of shape. Not sure if it was true but it made sense.

So I wonder if a bow shooting at 40-50 degrees would shoot faster versus slower at say 85-100 degrees. That's a large difference in temperature. My bow is actually tuned in at 85-100 degrees here in Bakersfield. When I go up the mountain it's around 40-55 degrees in the early morning. Hell, I don't really know but it's something I have been thinking about.

 

[Wild1]

I've never noticed any difference at elevation, and either has anyone I've hunted with. Are you sure you're not talking about shooting at a target that's above, or below you….?

 

[mattys281]

I live in phoenix which is 1,100ish and hunt up in the 8-9,000 area. I always check my 40-60 pins and sometimes adjust at camp. Sometimes I don't have to make a move. Don't know why. Elevation+humidity+temp??? Who knows. I like to shoot a few at camp for confidence anyway, so if I think I need an adjustment I move it and then end up moving it back when I get home again.

 

[JustGuy]

There is no difference in elevation, however, there is significant difference in temperature since it effect the sting length, hence poundage of the bow.
The higher the temperature, the slower the bow.

 

[TheGDog]

Regarding scientific factors which could influence the arrows flight... well.. colder air is more dense and thus could present more resistance... but at the same time... when you are at higher altitude the air is less dense to begin with. think of it like this... if you are at sea-level... air-pressure is something like 15 Lbs psi. And what creates that pressure, among other things, is the force of gravity pulling all those air molecules down towards the Earth. When you're at sea-level... if you were to imagine like a long straw that went up from the Ocean's surface... that went straight-up from that point on the Earth...way up to just past the atmosphere... Approx 300 miles (thought most of the atmosphere 80% is contained within those first 10 miles up)... the psi you'd measure at the bottom of that straw is from the weight of all those air particles pressing down upon it. The higher you go... the less amount of air particles there are on top of you, thus lesser ambient air pressure.

If that arrow is being met with less resistance... theoretically it should be able to travel a slightly greater horizontal distance overall. So let's say the highest point in the arch of its flight path... with its current sighting-in... is like at 20 yds away... when using a particular sighting pin. With less resistance I could easily see the arrow reaching a further distance away from you as being the crest of the arch of its flight-path... thus.. if you are.. in particular focusing on where it shall hit on a target of an equal distance away both times... both as regular altitude/temp... and also at this higher altitude/colder temp... I could easily see the flight-path causing the arrow to hit the end target slightly higher. But by how much? I don't think the amount we be significant enough for you to perceive it with just your eyes.



P.S. - JustGuy... thank you for that insight on how temperature affects the bow string!

 

[jmoudy]

I've never noticed any difference at elevation, and either has anyone I've hunted with. Are you sure you're not talking about shooting at a target that's above, or below you….?

My target that I tested a few arrows with was pretty much horizontal to me. They hit 2-3 inches higher than they normally would below at home.

The buck I missed at 60 yards was way below me shooting down at it. I used my range finder with angle/tilt technology built into it.

 

[mattys281]

My target that I tested a few arrows with was pretty much horizontal to me. They hit 2-3 inches higher than they normally would below at home.

The buck I missed at 60 yards was way below me shooting down at it. I used my range finder with angle/tilt technology built into it.

Thinking back on it now, the tilt compensation could explain why I had to adjust one year and not the next. The first year my campsite was at the base of a hill, so I probably had some elevation change between me and the target. Net change was only 2-3" at 60, so wasn't huge anyway. The next year I was camped in a different spot, probably flatter. Sometimes way up in the mountains a "flat" spot is not actually that flat, just looks like it is compared to the steep ridges around you.

 

[OPAH]

Is there a chance this Is being way over thought, when you have a 6" kill zone and you are accurate what is the difference 1 or 2 inches is going to make. but I have shot my bow at distance up at hunting altitude and have not seen that big a difference.
But hey get up there jack with your Bow settings all you want, temp and humidity change by the hour, sounds like a really good way to have a unreliable set up. Think long think wrong ! If it is not broke don't fix it, some times it wise to let well enough alone

 

[JustGuy]

Temperature of above 100F compared to 75- 80F when i shoot at my range gave me more than 6" drop at 40 yards.
Maybe not all of it was attributed to the temperature(increased string length) but still it is significant shift.
I know one thing, try to take your bow from a of car's trunk where the temperature is very high, shoot and see the difference yourself.
Also i heard that, double cam bows are less effected by temperature than single cam ones.

 

[OPAH]

Maybe that's It my aging double cam Proline Is still a bow that gets It done Hot, Cold, High , Low.

 

[bsanders8181]

5000 feet in Reno, vs 1000 feet in Sonoma County no difference 15-60yds. Bowtech Assassin binary cam. Relatively equal temp, humidity is much higher in CA though

 

[hunterdoug]

When I lived down below I believe I noticed that my arrows flew different, I now live at 6050ft, yes they fly different, bring your target...change 15 or 20 yrd pin the rest will fall in line...

 

[jmoudy]

I've done a couple searches online and tested my accuracy at the higher elevations the last time I went out. I've come to the conclusion that if your bow is tuned in at a lower elevation and higher temperature zone than you hunt, some bows (ok, some not all) will shoot differently at a higher elevation/lower temperature. It's just science/physics. For example, tomorrow I'm going out and will go from 400-600ft elevation to roughly 7500 and a temperature drop from 90-100 degrees to 40 degrees in the AM. My bow is tuned in at the lower elevation/higher temp. 7000ft and maybe 60 degrees in temperature difference. It has to impact the bows performance in some capacity or another. At 30 yards probably not so dramatic but get out to 60 yards there has to be a difference. I'm going to test it out at the longer distances tomorrow.

 

[Revo2811]

I'm a believer in this. I shoot a bowtwech invasion . I'm at 1800' elevation when I go to 8000' there's is a difference . Why would you want to guess . I want to hit what I am aiming for not hope or assume.
All you you have to do is take a target very easy . You'll get that one chance on a buck and miss than you'll ask your self why and how?



?