Ballistic app not same as the shot? Help

[Lone Hunter]

Measured the diameter of scope and diameter of bolt. Took half of each of those measurements added to the distance between the scope and bolt. Dia. Of scope was 1.718 so half of that was .859 bolt was .698 so half of that was .349 and the distance between them was 1.125 add together and get 2.333 could it be because of the 20" barrel? I see no place to input length?

I believe that your muzzle velocity is off. You can true up velocity and come ups on StrelokPro. You have to put in the proper numbers to get good data. If you go off what the MV is on a factory box you are screwing up. Get a chronograph or borrow one to get the correct MV and I bet your data will be a lot more accurate. The old saying "Garbage In, Garbage Out" is a true saying. It's all math, put in the correct numbers and drops will line up. Also, if you can go further than 150 yds you will be able to see how your come ups match velocity.

 

[Nuclear Worker]

Ya that speed is prob from a 26" barrel. I'd bet around 2500 ish is more real.

In the app we put it at 2300 and it matches what she was doing for clicks. Have to put the magneto on and see. Waiting on the suppressor which will add 5" to length. Only 50 rounds through it so it should pick up some speed yet correct?

 

[Bob Wright]

Measured the diameter of scope and diameter of bolt. Took half of each of those measurements added to the distance between the scope and bolt. Dia. Of scope was 1.718 so half of that was .859 bolt was .698 so half of that was .349 and the distance between them was 1.125 add together and get 2.333 could it be because of the 20" barrel? I see no place to input length?

No, not on Strelok for barrel length. Has to be inputs into Strelok somewhere I would
think.
When you selected your scope and reticle for inputs and clicks, was it exactly what you have? I'm thinking it's defaulting back to something only in 1/4 moa, somewhere.

 

[Bob Wright]

Measured the diameter of scope and diameter of bolt. Took half of each of those measurements added to the distance between the scope and bolt. Dia. Of scope was 1.718 so half of that was .859 bolt was .698 so half of that was .349 and the distance between them was 1.125 add together and get 2.333 could it be because of the 20" barrel? I see no place to input length?

I think you measured the bell or ocular of your scope at this diameter:
"Dia. Of scope was 1.718 so half of that was .859"
It is probably 1.0 inch or 30 mm for the main tube.

 

[Nuclear Worker]

No, not on Strelok for barrel length. Has to be inputs into Strelok somewhere I would
think.
When you selected your scope and reticle for inputs and clicks, was it exactly what you have? I'm thinking it's defaulting back to something only in 1/4 moa, somewhere.

After putting in a slower velocity of 2300 it matches what she was doing for clicks. I didn't put the chronograph on it yet because wanted to get some rounds down the barrel and was waiting for the suppressor. But I think the 20" barrel is the culprit. Just looked up what they use for testing velocity at the factory and it's 25"" we'll see this weekend hopefully

 

[Nuclear Worker]

I think you measured the bell or ocular of your scope at this diameter:
"Dia. Of scope was 1.718 so half of that was .859"
It is probably 1.0 inch or 30 mm for the main tube.

What would it matter the center of the ocular would still be the center of the main tube?

 

[Nuclear Worker]

Using the main tube instead only changes by .189

 

[Bob Wright]

Using the main tube instead only changes by .189

The numbers threw me. I just measue off of main tube.

 

[Bob Wright]

5" shorter barrel is generally 125fps (25 fps per inch of barrel) difference. In general....
Does that coincide with your actual drops you're seeing.

 

[Nuclear Worker]

5" shorter barrel is generally 125fps (25 fps per inch of barrel) difference. In general....
Does that coincide with your actual drops you're seeing.

We were using 2700 which was factory spec's. I kept inputting slower speed until it was showing 8 clicks for 150 yards. Which is what she needed for the shot. I have to put on the chronograph and confirm. She is zeroed at 100. Now we were shooting if off a slight hill at 150. Used the angle feature on the app and it showed zero angle for the shot as the target is on a slight rise also. Seems really extreme to need 8 clicks at 150 yards when zeroed at 100 doesn't it?

 

[Nuclear Worker]

We were using 2700 which was factory spec's. I kept inputting slower speed until it was showing 8 clicks for 150 yards. Which is what she needed for the shot. I have to put on the chronograph and confirm. She is zeroed at 100. Now we were shooting if off a slight hill at 150. Used the angle feature on the app and it showed zero angle for the shot as the target is on a slight rise also. Seems really extreme to need 8 clicks at 150 yards when zeroed at 100 doesn't it?

It's becoming apparent that we have a lot of variables right now that we have to remove for accurate information. Again we are new to the target shooting game so I have never had these problems before. For all our hunting rifles if you can hit the 4" or 2" gongs you were good to go. For the same shot with my 6.5x284 is only up 1 click at 150 yards. Now I know mine is 1/4 clicks and hers is 1/8 which would be pretty close to the 4 clicks the app called for so I'm hoping the shorter barrel turns out to be why it took 8 clicks for the shot.

 

[Bob Wright]

We were using 2700 which was factory spec's. I kept inputting slower speed until it was showing 8 clicks for 150 yards. Which is what she needed for the shot. I have to put on the chronograph and confirm. She is zeroed at 100. Now we were shooting if off a slight hill at 150. Used the angle feature on the app and it showed zero angle for the shot as the target is on a slight rise also. Seems really extreme to need 8 clicks at 150 yards when zeroed at 100 doesn't it?

For 50 extra yards, it's ridiculous. Something ain't right.

 

[Taylorbok]

It's becoming apparent that we have a lot of variables right now that we have to remove for accurate information. Again we are new to the target shooting game so I have never had these problems before. For all our hunting rifles if you can hit the 4" or 2" gongs you were good to go. For the same shot with my 6.5x284 is only up 1 click at 150 yards. Now I know mine is 1/4 clicks and hers is 1/8 which would be pretty close to the 4 clicks the app called for so I'm hoping the shorter barrel turns out to be why it took 8 clicks for the shot.

I guess it's believable that you are only running 2300fps. Barrel will speed up after about 150 rounds. Velocity looks to be your only major issue from what I can see. BC on bullets might be off a touch.

 

[Bob Wright]

I Iooked at a scope you quoted on your previous post. It shows in MILs, not MOA. Is MILs what you have? It should say on the scope adjustments. If so, each click is part of a mil. usual clicks are .1 mils, .36 inches at 100 yards.
Can you verify you have either?