Sighting in, Best distance

You say it's your first air rifle... Your best bet without getting complicated is to put a target at a couple known distances and shoot some groups and note the results and how they relate to any markings on your scope.

Otherwise the info you need for chairgun is pretty much the same info we'd need to help. What weight pellet at what speed (would need a chrony) would be the basics. There are ways to estimate speeds by back calculating the measured over/under results on target vs distance but still an estimate
 
We see this question a lot in all shooting sports. There are many variables, so unfortunately the answer isn’t quick and easy. An app will help since it allows you to put in the variables needed to answer the question. People often post their own trajectory charts, but they should be used as a general guideline.

Without knowing pellet weight and speed if would be very hard to say. Shooting a low powered 22 would have a different impact from a high powered 22. 

Sorry we can’t give you a better answer, but in genera It is probably still rising all the way up to 25yds.
 
CCman

When I set up a holdover card for my scope wheel. I always shoot and record my holdovers at every yard till it get's pretty flat with my sight in zero.

I always zero mine at 28 yds just because I like to shoot benchrest cards and it's also about the halfway point out to the 55 yd mark used in Field Target.

With a 25 yd zero you should be pretty flat from 20 to 30yds . Before and after that you will notice the pellet drop. Just hold your crosshairs on the zero sight in at 25 yds and look at where your mildot is during each individual shot and write it down on paper. I usually shoot a 3 to 8 sht group for confirmation, especially at the longer distance.

Here's a target paper that I used on my Thomas to record the holdovers. It was close enough to still call it flat at 23 to 24 yds so I didn't bother with anything between there and 30 yds.

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Then just write your hold overs on a card and attach it to or keep it with your rifle. I keep mine hooked to my cheek piece.



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Got my yardages marked on my 6 inch scope wheel.

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I actually have been sighting in at 11 yards. Seems to work out for me and is fairly consistent with strelok pro with my hold overs/unders. For example with my vulcan .25 I zeroed at 11 yards and it zeros back out at 80 yards. I used to zero out at much farther distances (60 yards or so). I also have a short indoor range setup in my house. Down the hall and into the garage. Also I try to avoid causing issues with the neighbors. I still shoot outside in my yard but I keep it to a minimum. Even with such a close sight in distance when I go out everything still works out and little adjustment is ever needed. Why you might ask why 11 yards? Well that just happens to be how far my target to my rest was so I went with it. I did see a lot of posts around the net saying to sight in your airguns at 10 yards. Ideally I think this is old school but not sure. Just pick a distance within reason ad go from there. Im sure you will get a lot of different opinions. I did when looking into it years ago.