Author Topic: Aim point adjusting for distance  (Read 1244 times)

Alan

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Aim point adjusting for distance
« on: February 04, 2020, 03:46:03 PM »
Any new airgun and/or scope setup, is going to require modifying one’s memory with respect to hold over and/or hold off for wind. This fact opens up a can of worms, because there are several (pet) ways to compensate for both distance and wind conditions. All of this fiddling around may be easier for guys who use their turret adjustment for distance, as I was once taught. But… I have long-since learned, that fiddling with the turret, while trying to shoot a moving target, is a sure-fire way of missing your game (pun intended)!

Perhaps just as interesting, are those who use their reticle’s markings (MRAD or MOA) for windage, and their turret for distance. That scenario, I have never understood. After all, there are very few top turrets large enough, to accommodate marking for proper distance. As a result, I’ve learned to use the scopes reticle markings to adjust the holdover, and windage when needed.

Digressing for a moment… When I first learned to aim and shoot while sighting through a scope, scopes didn’t have much more than just cross hairs. In fact, multiple reticle markings are a late-model improvement in some respects. In fact, I can’t think of a single scope I purchased, say previous to 1980 or so, which had range and windage markings.

Our firearms companions, can buy an automatic, range-finding, electronic scope, which lights the appropriate LED on the reticle, for exact POA. Wonderful invention, but unfortunately, airguns are a bit slow in velocity for these types of scopes. Hopefully, one day they’ll get the message, and make some of the digital wonders for us folks! I’d buy one, at least.

All of this rambling brings forth the method “I” use to adjust for distance, and windage when needed—the range card.

Below is one I assembled from scanned images. There are computer programs which will do this for you, but I don’t own one. Hence the hodgepodge I came up with. Note, that there are no nomenclated hold offs for windage. Doing so is a bit of a guessing game, as the wind velocity near you, may be vastly different down range. Unlike Field Trials, placing wind vanes hither and yon isn’t an option. So, I guess! I must be fairly good as it, as I typically hit what I aim at. Call it experience! But distance, not so much!

I use a laser rangefinder, as almost every long-distance air gunner does. Since I hunt (shoot) in the same general areas repeatedly, I generally know what the distance to target is, without using the rangefinder. Regardless, it is no sin for any of us to use our laser rangefinders. Once I know the distance, what do I do? The answer is… I use my home-made range card.

I know the photos isn’t as clear as I see it on my end, but least you get the picture (pun not intended). 

I’d like to know what the reset of you use, if at all???




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Alan

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rsterne

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Re: Aim point adjusting for distance
« Reply #1 on: February 04, 2020, 05:57:01 PM »
I use ChairGun and print the "Scope Cap" chart for the reticle I use, at the magnification I use for shooting past my 2nd zero, for the pellet and velocity the gun is set for.... I use the "size" setting for the chart so that it fits on the appropriate pellet tin, and print it on a label.... From 15-40 yards I can hold dead on....



I get to cheat a bit because all three of my Varmint rifles in .22, .25 and .30 cal are set to the same velocity, and all shoot JSB Exact pellets, so the BC is close enough that for practical purposes they have the same trajectory.... I use exactly the same model scope on all three rifles, a 3-12X, and it just happens to work out that I can sight in so that at 100 yards the POI is at the top of the lower post (so 5 MilDots down)….

Bob
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Steelhead

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Re: Aim point adjusting for distance
« Reply #2 on: February 04, 2020, 08:04:33 PM »
This is and will be an ongoing issue for me. I have some hand drawn charts that I tape onto my Texan. Being as how I shoot vastly different sized ammo (110 gr. to 150 gr.) at vastly different ranges (50 to 300 yards is common) it's always a thorn in my side. The range is one thing, in the field is another. My first shot has to count. I'm always playing with my distance zero depending on what I'm doing and I just can't remember where I'm at. The difference in POI at 200 yards between the 110 gr. and 150 gr. is measured in feet, not inches.

I have to have an updated chart on the gun at all times or I just forget where I'm at with all of the variables.
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Alan

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Re: Aim point adjusting for distance
« Reply #3 on: February 05, 2020, 06:55:43 AM »
One issue I have, is the fact ChairGun will no longer run on Mac OS 10.15 (Catalina). The reason is, it requires JAVA 6.0, which won't run either. The versions for a iPhone and iPad, don't have the "Scope Cap" printout. I have Ballistic AE for my iPhone, but it doesn't have the feature either. What you see was a culmination of Strelok data, and a jpg of the Hawke reticle.

What I'd like to have, is a decent ballistics program for Mac OS (non-iOS), but no one publishes one. There are some really neat ones for old Mac OS versions, but alas not for 64 bit software.
  • Roswell, New Mexico
Alan

I have an Omega compressor. If you're a fellow Guild member, and you pass through Roswell, NM, I'll fill your portable tank as a courtesy.

Steelhead

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Re: Aim point adjusting for distance
« Reply #4 on: February 05, 2020, 07:22:51 AM »
LOL!!! This is what I try to avoid. I don't feel so bad now. For this shooter a pen, paper, and some clear tape gets it done.

The interesting thing is how different shooters come to the same result using different methods. The target nor the quarry gives two shits about how the projectile gets there. Turret turners, hand writers, computer-philes, etc. all get it done in their own way.
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Benjamin Prowler .177
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steveoh

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Re: Aim point adjusting for distance
« Reply #5 on: February 05, 2020, 01:48:38 PM »
One issue I have, is the fact ChairGun will no longer run on Mac OS 10.15 (Catalina). The reason is, it requires JAVA 6.0, which won't run either. The versions for a iPhone and iPad, don't have the "Scope Cap" printout. I have Ballistic AE for my iPhone, but it doesn't have the feature either. What you see was a culmination of Strelok data, and a jpg of the Hawke reticle.

What I'd like to have, is a decent ballistics program for Mac OS (non-iOS), but no one publishes one. There are some really neat ones for old Mac OS versions, but alas not for 64 bit software.

The way to keep old software running is to use a Virtual Machine with the OS of your choice and the applications that reliability run on that OS. I keep an ancient version of Freehand running on an old server version of the Mac OS.
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steveoh

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Re: Aim point adjusting for distance
« Reply #6 on: February 05, 2020, 01:51:00 PM »
LOL!!! This is what I try to avoid. I don't feel so bad now. For this shooter a pen, paper, and some clear tape gets it done.

The interesting thing is how different shooters come to the same result using different methods. The target nor the quarry gives two shits about how the projectile gets there. Turret turners, hand writers, computer-philes, etc. all get it done in their own way.

I thought I had my Texan dialed in for various distances and printed out a cheat sheet that I taped on the Texan tank. Silly me, I changed scopes and now everything is whackadoodle.
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Alan

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Re: Aim point adjusting for distance
« Reply #7 on: February 05, 2020, 02:21:43 PM »
Steve, I should have left the old iMac mushroom, but the guy I sold it to., paid me almost three times what I thought it was worth. Apparently, he's a Mac collector, and wanted it badly. It was working, by the way.

I really don't want to throw money at this, but there is a stand-alone ballistic calculator out there, that would do what I want it to so. But I thought the FX was expensive.....
  • Roswell, New Mexico
Alan

I have an Omega compressor. If you're a fellow Guild member, and you pass through Roswell, NM, I'll fill your portable tank as a courtesy.

rsterne

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Re: Aim point adjusting for distance
« Reply #8 on: February 05, 2020, 04:29:35 PM »
You can try Strelok Pro, which is an Android Ap.... There is a free version, but I paid for the upgrade (cheap), and from what I have seen, it is pretty good.... My biggest problem, as always, is lack of time to learn it....

Bob
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Alan

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Re: Aim point adjusting for distance
« Reply #9 on: February 05, 2020, 04:48:41 PM »
I have Strelok Pro for Mac. It is fairly easy to use, but it lacks some things I deem critical. If nothing else, it is the ability to down load ballistic info on PELLETS.
  • Roswell, New Mexico
Alan

I have an Omega compressor. If you're a fellow Guild member, and you pass through Roswell, NM, I'll fill your portable tank as a courtesy.

Alan

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Re: Aim point adjusting for distance
« Reply #10 on: February 25, 2020, 09:03:52 AM »
Here is what I finally came up with. Long story how things ended up at a 72 yard zero, but the shot story (pun intended), is it is two MRAD (mil dots) of holdover when shooting 100 yards. If you think about a 2 inch diameter kill zone, it makes a bit more sense. So, for me at least, a zero this far out has worked better than any other I have tried.


  • Roswell, New Mexico
Alan

I have an Omega compressor. If you're a fellow Guild member, and you pass through Roswell, NM, I'll fill your portable tank as a courtesy.