StrelokPro not quite spot on

Are you entering temperature barometric pressure? How about your ballistic coefficient that's hard to get accurate.

BC On Strelok is not always 100%, best to verify it and enter the correct details. It is in another post on here what to do. Have search and it should show up.

You need to have Strelok grab the weather before any calculations are made. Remember to click "use these values" whenever there is new data. As the weather changes throughout the day, let's say the temp goes 20 degrees, you should consider updating the weather.

Also, make sure to click on Enable zeroing weather. And any time you zero your scope at the start of the day and you make an adjustment to the turret, you have to grab the current weather and update it under the Zeroing tab if it was different from the weather you initially zeroed in.

From there you need to do a trajectory validation. This way if what Strelok gives you for hold over isn't accurate, you can make an adjustment so all the calculations after that will be spot on.

Bob, can you explain the trajectory validation process in a little more detail please?

jk

Sure.

After you properly enter all your data as accurately as possible, and zero the rifle with the current weather conditions, you set up at target at a further distance....I like to use 100 yards.

Have strelok calculate the shot for you and then take the shot with the amount of hold over in the calculation. 



If you hit the bullseye at that distance there is no need to do a trajectory validation. However if the shot is high or low then you will need to perform this action.

Let's say you entered a BC of .08 and took the 100 yard shot according to what strelok gave you and the shot landed High. You would then make a turret adjustment or a hold over adjustment for the shot to hit the bullseye. You then take note of the actual amount of clicks or hold over and then go into the trajectory validation tab in strelok.



In the above SS you can see the old BC of .08 and the amount of elevation Strelok said to use.

At this point you, in the SS below, you enter the actual amount of hold over that was used and have strelok calculate a new BC.



You then click the button to have strelok use this BC, and it will then give you accurate calculations for all future shots at various ranges under those conditions. 



In this SS you can see that Strelok has now calculated a new drop based upon the new higher BC.

You only need to perform this validation one time. 

It can get more involved it you want to, but this is what I do for my purposes and it works just fine.

If you're shooting pellets, be sure to use the drag profile GA. For slugs you would use G1.

You may be right, I should update the barometric pressure & temp. As for the ballistic coefficient, it was in the StrelokPro app.

Click to expand...

The default BC is normally off by a bit. For instance, my validated BC for JSB 18gr pellet at 950fps was .058 instead of the default value of around .036.

My first thought is the scope height above the bore might be off. Just an idea.

It could be that or a few other things. 

This is why it's so important to set up Strelok as accurately as possible. Also to make your zeroing and trajectory validation shots from as stable a rest as possible.

It's not at all uncommon for a chrony to be off by 20+ fps.

It's not at all uncommon for a chrony to be off by 20+ fps.

Click to expand...

True.

In the trajectory validation function, you have the option to validate velocity instead of BC.

Problem with that (in my case) is if I go to validate using velocity, Strelok has given it 100fps faster than what my gun is capable of. 

Same with my powder burner. It will tell me my rifle with a short barrel is shooting faster than the stated velocity for that round using a gun with 8" longer barrel.

That's why I always validate the BC after I've chronographed it myself.

Great explanations Bob. Thanks a bunch. I will bookmark this for sure.

Me too, great explanations Bob 

It might just be in a different location.