Ballistic Computer Trajectory Validation Trick!

[Palmetto-Pride]

Ok so you ever have one of those Ah Ha moments when you figure something out and then realize it should have been pretty obvious. For those of you that use ballistic apps or computer programs one of the biggest things I have noticed is most of them don't have a trajectory validation option. The trajectory validation option is when you tell it what the actual elevation adjustment that was needed when shooting vs what the program originally calculated for you. It then takes that data and adjust your velocity to make it more accurate across the board. So here is the little trick I figured out for programs that don't have the Trajectory Validation Option. What you can do is when shooting and you have your actual elevation adjustment required you can go back and manually adjust your velocity until the solution it gives matches what your actual adjustment was I know this seems simple and maybe a lot of you already thought of this, but I just figured it out Anyway hope this helps someone who was as dim as I was......lol

[kraigwy]

First I will start by saying any BC program has to be checked with actual shooting at the range.

But even that changes. Temp. changes, humidity changes, elevation, etc. All change the trajectory of your round. Even data books only get you close.

Take your BC program and don't change anything but the Altitude. See what does to your trajectory.

Try the same thing with humidity.

I have a G7 range finder. It has a weather station built in, where you put in your velocity, the bullets BC, and the scope height. Then it automatically takes in the environmental conditions and gives you the adjustment you need (up to 1400 yards.)

Its fun to compare the G7 with the Shooter Program on my IPhone. Take a distance of 800 yards. Sometimes the G7 agrees with the BC program, sometimes it calls or less change for elevation, and some times it calls for more then the BC program.

With your BC programs you also need a "weather station" and put in the conditions at the time you pull the trigger.

The G7 doses that automatically. When you range a target, you get the distance then the elevation changes pops up.

Great for hunting or a Precision Rifle Match where you don't have the time to fire up your slide rule to figure the changes.

But BC programs G7 Range finders, data books, or what ever, you need actual shooting to confirm the accuracy.

We didn't have all these fancy gadgets when I first got into Army/LE sniping.

Makes me wonder how I ever hit anything.






T

[wogpotter]

Agreed about external influences like altitude, humidity & so on.

Funnily enough I have a Leatherwood ART scope which has an auto ranging/BDC system built in.

One of the things they have in the manual, right after the section where you adjust the setting calibration for bullet path is a validation section where you actually "tweak" the basic caliber/BC/range setting to match your actual trajectory out to 600 yds (assuming you can find 600 yds to shoot)

[Palmetto-Pride]

Yea I know they are not always going to be dead on and I realize that for them to be as accurate as possible you need to enter in every bit of data as accurately as possible. The program that I use most is MIL-Dot Ballistics on the iPhone 6 which as a built in barometer and GPS and it pulls the rest of the data from the closest weather station. When you zero your rifle and load combination you can enter your "zero conditions" by hitting one button and when you use it another day/place you can hit the "current conditions" button which will obviously take into account your "zero conditions" vs your "current conditions". I have only used it out to 600yds and it is usually within a 1/2 mil (10.8") and a lot of times it is dead on. It gets me close enough usually where I don't need a spotter. I know 600yds is a joke for most of you, but for me to shoot further its about a 3hr ride 600yds only about 1.5hrs.