Ballistics program help

[straightshooter412]

I am using Strelok Pro calculator attempting to get the correct scope adjustment for 333 yards. This is the longest yardage I have to shoot while practicing. My confusion comes into play when I input all the data and get conflicting information. At least it is conflicting to my head.


My scope is a Mil-dot, SFP- 6 x 24, 1/4 @ 100 yds., sighted in at 200 yds, scope height 2.07 inches, MOA .25, bullet speed 2801 fps @ 59 deg F, SF= 1.12, coefficient used is G7. Bullet is a 270 Win SST 130 gr, ballistic tip.


Using a F-class - long range target on the program and calculate it presents me with MOA - 2.8, MRAD 0.8, inches U10, clicks U11 on main screen.


After I calculate and switch to reticle mode, with 24x, 0 MOA selected, it shows me 2 mil dot = 331 yds. not 0.8. This differs from data on the main screen as noted above. Is the number of clicks correct? I keep shooting low when this is dialed in.


Can someone help explain why I am getting this information that is so different? I would truly appreciate it.

 

[CharlieNC]

Going from 200 to 333yd, 0.8mil should be close. On the reticle view with a SFP scope did you spec your exact scope model, and confirm the magnification where the reticle is accurate vs the mag used?

 

[Depart123]

There could be a number of things going on. 1) You may have a zero offset input from another session. Touch your bullet speed and scroll down to make sure 0's are there. 2) double check scope height and zero. 3) when you go to the reticle menu, if you have SFP selected then make sure your slide at the bottom of the screen is all the way right to 24x. 4) The turret at the top of the reticle in that screen moves to input offsets directly. Make sure that is at 0 moa also.

CharlieNC is right. With that much variance there is an issue with the zero somewhere.

 

[straightshooter412]

There could be a number of things going on. 1) You may have a zero offset input from another session. Touch your bullet speed and scroll down to make sure 0's are there. 2) double check scope height and zero. 3) when you go to the reticle menu, if you have SFP selected then make sure your slide at the bottom of the screen is all the way right to 24x. 4) The turret at the top of the reticle in that screen moves to input offsets directly. Make sure that is at 0 moa also.

CharlieNC is right. With that much variance there is an issue with the zero somewhere.

There could be a number of things going on. 1) You may have a zero offset input from another session. Touch your bullet speed and scroll down to make sure 0's are there. 2) double check scope height and zero. 3) when you go to the reticle menu, if you have SFP selected then make sure your slide at the bottom of the screen is all the way right to 24x. 4) The turret at the top of the reticle in that screen moves to input offsets directly. Make sure that is at 0 moa also.

CharlieNC is right. With that much variance there is an issue with the zero somewhere.

Thanks to you both for the quick reply. Deer season opens Saturday. I have checked the zero offset under bullet speed and it is set to zero. I double checked the scope height and zero, right on at 200 yds. With SFP checked, the mag is set to 24 x, and the MOA at the top is at zero. The scope I have is an inexpensive one "Sniper", model # - LT6 2x24x50AOL. The closest I have found to match up in Strelok is either US Army Mil-dot or Vantage 6x24 Hawke on the reticles. As before, at the main screen on Strelok, MOA - 2.8, MRAD .8 inches 10, Clicks 11. moving to the reticle screen - the mil dot indicates 2 mils at 334 yds. Still can not figure out why it shows 0.8 MRAD on main screen and 2 mils on the reticle screen. Which would I use?

 

[DocUSMCRetired]

We have some resources, including a firing solution checklist that might help you out. Take a look here: www.appliedballisticsllc.com/articles

 

[CharlieNC]

The ballistic calculation is correct. The problem is applying the results to your reticle. With SFP the mil dots are calibrated at only one power; I don't know what that is for your scope and the manual should prescribe this. This means if you use a different power on the scope, then you need to compensate for that power vs the calibrated power. When setting up a sfp scope in Strelok you need to tell it the ranging magnification (the one the mil dots are calibrated for), and then the mag you are using in order to translate the ballistic calcs to the reticle.

 

[VaRandy]

I am using Strelok Pro calculator attempting to get the correct scope adjustment for 333 yards. This is the longest yardage I have to shoot while practicing. My confusion comes into play when I input all the data and get conflicting information. At least it is conflicting to my head.


My scope is a Mil-dot, SFP- 6 x 24, 1/4 @ 100 yds., sighted in at 200 yds, scope height 2.07 inches, MOA .25, bullet speed 2801 fps @ 59 deg F, SF= 1.12, coefficient used is G7. Bullet is a 270 Win SST 130 gr, ballistic tip.


Using a F-class - long range target on the program and calculate it presents me with MOA - 2.8, MRAD 0.8, inches U10, clicks U11 on main screen.


After I calculate and switch to reticle mode, with 24x, 0 MOA selected, it shows me 2 mil dot = 331 yds. not 0.8. This differs from data on the main screen as noted above. Is the number of clicks correct? I keep shooting low when this is dialed in.


Can someone help explain why I am getting this information that is so different? I would truly appreciate it.

 

[VaRandy]

Since your scope is MOA why are you talking milrads?

 

[straightshooter412]

Since your scope is MOA why are you talking milrads?

If I do not have time to dial in the distance I can use mils for quick reference and shot.

 

[straightshooter412]

The ballistic calculation is correct. The problem is applying the results to your reticle. With SFP the mil dots are calibrated at only one power; I don't know what that is for your scope and the manual should prescribe this. This means if you use a different power on the scope, then you need to compensate for that power vs the calibrated power. When setting up a sfp scope in Strelok you need to tell it the ranging magnification (the one the mil dots are calibrated for), and then the mag you are using in order to translate the ballistic calcs to the reticle.

The ranging mag is 10x and has been imputed for calculation.

 

[6ShotsOr5?]

Agree with CharlieNC. Also, every SFP ranging reticle I have seen has the reticle markings calibrated for the max magnification of the scope. Also check the owners manual to make sure what the actual maximum is. For example, I have a scope that is labeled as 8.5 x 25, but the actual specifications in the owner's manual are 8.2 x 25.1. In that case, you would use 25.1 in the app instead of 25.

I'm confused by the information you gave us. It sounds like you are saying you have a mil dot reticle but a 1 click = 1/4 MOA elevation turret. Is that correct? If that is true and the program is giving you a 0.8 mil solution, then you have to dial for 2.8 MOA not 0.8 mil because you have to dance with the turret that brung you. If you are trying to dial 8 clicks like you would if you had a 1 click = 0.1 mil turret then you will be low, because 2.8 MOA with you turret would be 11 clicks, not 8.

 

[CharlieNC]

Well if the calibration is 10X and you are using 24X then the reticle point you are shown is correct. 24/10*0.8 = 1.92 which agrees with the 2mil Mark you indicated. On a sfp scope as the mag increases the mil dots subtend less; you can see this if you look at a target and vary the magnification. Actual mil spacing is only accurate at 10X on your scope. At 20X the dots are 0.5 instead of 1.0 mil.

 

[Depart123]

Yep, CharlieNC beat me to it. That's the only thing left it could be, and the math matches what you are seeing.

 

[straightshooter412]

I figured it out. Yea. All reticle measurement is based upon the ranging magnification, if ranging is set to 24x then at 24x power the reticle shows 1.3 mildot on the scope just as the main window shows. If I change back to the scopes actual ranging magnification, which is 10 x and put the scope on 10x power then it reads 1.3 mildot and on 24x it reads 3 mildots. I can not explain why the program does it this way, but I am sure it has to do with the math.
Thanks to everyone hat tried to help me .