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Hi everyone I'm trying to make a dope card for my load. I know if I shoot out to 590m I have to dial 16 moa up and 1 right. Do I have to manually shoot out to different distances to get the data or can it be calculated. I'm sure it can i just don't know how to do it
If you know the exact zero distance, height over bore, bc of the bullet, and the amount of drop you have at 590m, then you can punch the numbers into a ballistic app like strelok or a website like JBM to fill in the gaps, work out the velocity, and work out what drops will be.
Bullets follow steady arcs. If you know two points, you can calculate the rest.
There are plenty of ballistics apps available that will calculate what you want, and some are free. Shooting should be the most accurate for your rifle and your scope (e.g your scopes clicks may not be exactly 0.25 MOA).
As above you can use an online ballistic calculator like JBM ballistics, knowing your zero and drop at 590m is enough to work it out.
A phone app like Strelok Pro will even work it out for you with the two data points.
You'll probably want to confirm it at few other distances to be certain though.
Why do you need 1moa of windage at that distance? That is quite a lot if it's not accounting for wind.
What scope are you using? It may be worth checking the turret tracking to see if it's accurate/tracking perfectly vertically.
Scope isnt straight:thumbsup:Quote:
Originally Posted by Beetroot
Do you mean you have actually shot at 590m and adjusted up 16 and right 1 to hit centre ? What range did you zero at ?
In principle you can do it like this:
Sight in so your shots are hitting exactly on the aiming point at 100m.
Test your sight adjustments by dialling up 20moa and shooting a 5 shot group. This will tell you if your clicks are properly moa based or a little out. If there is some horizontal movement too its likely your scope or hold arent vertical. In practice its hard to be sure of something like a 1 moa difference unless youre a past master bench rest shooter.
Then put an approximate muzzle velocity and the best estimate of BCyou can get into a ballistic app. Double check all other inputs like scope height, atmosphere temp etx are the correct units and values. Use that to get a preliminary come up value to hit the target at about 600m measure ghe range very exactly by careful use of rangefinder because its critical.
Fire a 5 shot group at 600m and then adjust the amount you need to hit dead centre. Use a big piece of paper. Very big. Fire as many 5 shot groups asyou need, to establishthe group well centred for elevation. Dont worry about horizontal at 600m because wind will move it. You e established your windage zero at 100m.
Then go back to your ballistic app and adjust the mv input till it predicts the actual elevation come up you needed. That is your working muzzle velocity. Many apps have this as a function built in feature and is called “truing”.
Then you can use the app to estimate required come up adjustment for any other range. And if you feel clever you can use the predicted trajectory to sight in At any other distance and set your 100m zero again.
D.O.P.E literally stands for data on previous engagement. But colliquially its used for a set of calculated elevation adjustments to round numbered distances like 200, 300, 400 m which you have never been able to shoot at in real life. Usually people also include wind drift numbers at each range for some standard amount of wind like 5 m/s and perhaps an adjustment for slope-at say 300m and 30 degrees and somthing for a different altitude eg sea level and 1000m.
Its avery good idea to verify the dope chart by shooting at a variety of distances slopes wind etc to check. Also good fun !