WHAT YARDAGE FOR ZEROING

[Airgun-hobbyist]

I like a 40 yard zero. It has just the slightest bit of hold-under at 33 yards, but in all actuality it is less than the thickness of the pellet. At your pellet's speed a 40 yard zero carries a 2" arc from 12 yards to 52 yards, and only a 1" arc between 17 and 47 yards, which is ideal for hunting in the woods. No matter what the zero is, get a "dope chart" printed (with the zero that you settle on) and you'll have the required hold over elevation for given yardages at your fingertips for shooting or studying. FYI, the Windage Inch in the chart is for a 5 mph cross wind.

 

[KatoKevin454]

Wow, now I know why I am getting A.D.D.... Info overload, my brain cell hurts.......

 

[cavedweller]

I received a new rifle yesterday and want to sight it in out to fifty yards as that’s my self imposed limit, and pretty much the farthest my hunting area would allow because of trees and vegetation.
My desire is to zero the rifle so I just have come ups where all my distance variations from reticle center would be below the horizontal of the reticle. I don’t dial when pesting because I could to easily forget to dial (short attention span). I LRF my prey and then use come up dope.
The caliber is .30 at 848fps, 44.75 JSB Exact.
Appreciate any help on what’s the best way of going about that task.

Every gun is different - starting at 15 yards shoot a sighter every yard until you see your apex level off. Continue to shoot until your apex begins declining. See picture below - your zero should be the beginning or end of your pellets highest point. You can do this for different pellet weights to create dope charts.

 

[RickH]

It looks to me like all the tech being shown here is a bit much and over complicated. You want to shoot out to 50 yards. First shoot the gun at 10 yards and get a zero. It will take a calibrated eyeball but won’t take long. Shoot from a benchrest of some kind. Next try a few different pellets or slugs or whatever and find one that groups well in your gun. At this point you’ve eliminated 2 variables, a less than perfect freehand stance and you have ammo that your gun likes. If you are shooting a pcp then try to keep air pressure within a standard range for the next step. Now shoot at 20 until you have a zero. Then shoot 30, 40 and 50 getting zeros for each and staying in that air pressure range already mentioned. Write down all the come ups for each distance on a card and keep it with your gun. It will take some practice and a little Kentucky windage to figure out odd distances like 27, 32 and other distances between your set points. You’ll also learn a lot about a specific gun and about shooting in general. You can only spend so much time doing math problems and paying attention to ballistics before you find yourself figuring out numbers most of the time and not shooting very much. I caught myself making that mistake as a photographer. I realized I was screwing around with all the cool features on my camera and not taking many photographs. Don’t overthink it.

Rick H.

 

[Hateful McNasty]

Not rocket science but , I threw a scope on that was zeroed at 100. And wanted to example the 10m thing I posted above .

This gun using this pellet is pretty known values


At 100y I need to be at 10m 3.5" high

So for 50 I know it and 10 m are close to the same

So get on at 10m is pretty much on at 50y ..

Get on poa at 10m ( there's a hole in the dot)


Gives me this at 50y


Any gun and a set used pellet can do this at any range you want

Just know and what that gun will do with your preferred pellet.

I can use any known value of poi hight for what ever range I shoot from 10m

 

[dizzums]

without using an app, given your projectile speed is close to a nominal 900fps and scope height is 'average' most airguns will be around a 20yd zero for the longest point blank hold ... airguns have a pronounced 'two zeros' one at each end of the curve .. the closer poimt will be 20 .. the further one will be 45 or so in our 900fps/average scope height example .... zero at 20 ...at 50 it should hit a 1/2" lower, thereabout ..if its not adjust the '20' a yard at a time until it is ... anything outside the 2 points will be hold over, always, except in extreme angle/incline conditions which will tend to make it shoot high ..

 

[rcs9250]

without using an app, given your projectile speed is close to a nominal 900fps and scope height is 'average' most airguns will be around a 20yd zero for the longest point blank hold ... airguns have a pronounced 'two zeros' one at each end of the curve .. the closer poimt will be 20 .. the further one will be 45 or so in our 900fps/average scope height example .... zero at 20 ...at 50 it should hit a 1/2" lower, thereabout ..if its not adjust the '20' a yard at a time until it is ... anything outside the 2 points will be hold over, always, except in extreme angle/incline conditions which will tend to make it shoot high ..

Thank you.

 

[JimD]

If you know about how high the center line of your scope is above your bore I can run chairgun for you and provide some more accurate information. I tried 1.5, 2, and 2.5 inches. 1.5 may not be far off if you have a conventional rifle. 2.5 would be a bullpup.

At 1.5 inches the trajectory would cross over the line of sight from your scope at about 10 yards and again at 50 yards with a 50 yard zero (the first cross over point if different for a higher scope). The mid rise trajectory would be about an inch and a half at 35 yards if my memory is working. With a higher scope the mid flight rise would be less.

I do not like that much mid flight rise so I sight my airguns for shorter range. 30 yards works well for my P35s (bullpups). That is about the point of the maximum rise so I only hold over. I have to hold over out to about 20 yards although not much after 15 yards and again starting about 40 yards, maybe a little closer. I mainly shoot from 20 to 30 so for most shots I just aim and pull the trigger. If you are comfortable with a half inch mid flight rise, you could probably push the zero out to at least 40 yards and then 50 wouldn't be too far under.

 

[Vana2]

To throw in my 2 cents... Setup for an optimal trajectory (no compensation required) for the range you TYPICALLY shoot at.

I have a bunch of airguns (.177 & .22 caliber; springers, muli-pump and PCPs) and found that if I set them all up for the best "point blank range" (in Chairgun I use +/- 3/8" for a 3/4" nominal) then (typically) the pellet/slug will hit within 3/8" of the aim point anywhere between 17 and 38 yards.

So, I can grab any airgun and know that for 95% of my shots I can aim dead on and know I'll hit a pest, rabbit or squirrel. Close shots require a hold under, farther a hold over which can be learned, the rest is a no-brainer.

Bench shooting or long range (beyond 75 yards) pesting is dialing country.

Cheers!

 

[Berserkeley Mike]

If I wanted a PBR at the aim point with everything else held-over, and I didn't have a ballistics calculator, I might start with a rule of thumb to zero at 10 yards per inch of elevation of the sights/scope above the bore; for example, 10 yards for open sights 1" above the bore, 20 yards for a 2" low-mounted scope, 30 yards for a scope mounted higher at 3" above the bore, etc. That relationship seems to hold true for many guns and diabolo pellets moving at fast subsonic speeds.

 

[Sawney Bean]

I zero most of my rifles at 50 yards and this usually corresponds to somewhere between 10 and 20 yards for the near zero depending on the velocity and the scope height. This also usually gives about a 3/4" holdunder at the highest point of the arc, usually at around 35 yards. This allows me to shoot most of my rifles accurately out to 60 yards without much adjustment. I also keep dope sheets in the form of masking tape attached to the scope bell that list the exact holdovers and holdunders to what I consider the maximum effective range, so I can always easily check on what the actual trajectories are.

I do most of this by chronographing the rifles, then use ballistic software, (Element Ballistics), to plot the trajectory, and finally I confirm the accuracy of the plot by firing a few groups at various ranges to ensure the plots are correct.

There are four guns that I deviated from this with. My Hatsan 135, R7 and Barra 400E all have velocities that are too low for a 50 yard zero and my Sidewinder is just starting to stretch it's legs out at 50 yards.

I usually also keep data logs on my phone and pieces of masking tape attached to the outside of the gun cases listing the velocities with different pellets as well as the holdovers at different ranges.