Ballistic profile vs real world data

[Jon Boy]

I'm having a hard time getting my ballistic profile to match my real world ballistics any time I get past 700 yards. Once I bump up to 775 yards I'm a full minute high of what my ballistic app says to run. Which I find odd because it's dead nuts on all yardage up to 700. I haven't tried any thing in between 700 and 775. Have shot 800, 850 and 900 all with being one minute high.

I've messed with the bc, and all atmospheric conditions to try and replicate it but still am not coming close. The muzzle velocity has been checked via magentospeed and regular chronograph with the same results and ES of 10 fps.

Anyways if you guys are bored and want to run a load through your app lemme know what you come up with

7mm/08
162 eldm
Mv 2730
ES 10
5000 ft
50% humidity
Baro 30
Sight in height of 200 yards

At 850 my app is showing me 19.7 moa and in the real word 18.5 moa

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[ramont]

You probably need a ballistics calculator that allows you to adjust the BC of the bullet at those ranges. The better calculators allow you to adjust the point of impact at any range which the software then uses to adjust the BC value at that range.

 

[Gunnersdad49]

At thise ranges I’ve found that density altitude and sight height are the most finicky variables

 

[Formidilosus]

I'm having a hard time getting my ballistic profile to match my real world ballistics any time I get past 700 yards. Once I bump up to 775 yards I'm a full minute high of what my ballistic app says to run. Which I find odd because it's dead nuts on all yardage up to 700. I haven't tried any thing in between 700 and 775. Have shot 800, 850 and 900 all with being one minute high.

I've messed with the bc, and all atmospheric conditions to try and replicate it but still am not coming close. The muzzle velocity has been checked via magentospeed and regular chronograph with the same results and ES of 10 fps.

Anyways if you guys are bored and want to run a load through your app lemme know what you come up with

7mm/08
162 eldm
Mv 2730
ES 10
5000 ft
50% humidity
Baro 30
Sight in height of 200 yards

At 850 my app is showing me 19.7 moa and in the real word 18.5 moa

Sent from my SM-G965U using Tapatalk

What is the scope, and how did you zero at 200?

 

[Jon Boy]

What is the scope, and how did you zero at 200?

Nightforce Shv. Dead on at 200? Not sure if that's what your asking

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[Gunnersdad49]

What’s your scope height and barrel twist?

 

[Formidilosus]

Nightforce Shv. Dead on at 200? Not sure if that's what your asking

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Ok, scope is not where I would look first, but it isn’t just magically working at 700 and then at 775 it’s off a minute. Any uphill/downhill winds? How many rounds at each distance, and are you positive they are centered?


For zeroing I meant- did you/do you shoot a three shot group and call it good? 5 shots, etc.

 

[Jon Boy]

Ok, scope is not where I would look first, but it isn’t just magically working at 700 and then at 775 it’s off a minute. Any uphill/downhill winds? How many rounds at each distance, and are you positive they are centered?


For zeroing I meant- did you/do you shoot a three shot group and call it good? 5 shots, etc.

5 shots. 1 inch or less on a regular basis at 200 how ever I don't shoot much at 200 and havent done so in a while. Holds half moa at all distances as long as I do my part. I shoot at Clay's and keep a journal of conditions and corrections. Hit Clay's out to 700. Make it to 775, miss high, measure hit impact with reticle at 1 Moa, make correction and it's right in there. That's usually my process.

I have my corrections written down so not really a huge deal and at my hunting limit and in hunting conditions I'm fine. but it is nice to run a dope and use that dope when practicing in new areas

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[the0thermrt]

does your POI shift if you shift shooting positions?

 

[2five7]

Does your app allow for muLti BC? Bullet bc will change depending on speed. Some manufacturers average, some give the high velocity number.

 

[PowellSixO]

I've never had a ballistic program ever get my drops 100% correct. The further the yardage, the worse they usually are. The best way to do it is to shoot at multiple distances, as far out as you can possibly shoot. Then do the ballistic calibration with whatever software you are using. Then prove your your drops at each distance you plan on shooting, and run the calibration again if needed.

Another thing I learned from Formidilosus, is that 3 and 5 shot groups are not ideal for long range shooting. I now shoot 10 shot groups at each distance. The average between 10 shots is much more telling, than 3 or 5 shot groups. I've put multiple sub .5 moa 3 shot groups together from 100 yards, all the way out to 1010 yards (my best being a 3 1/2" group at 1010). But it's basically just luck. 10 shot groups tell the true story, about the rifle and the shooter. On average, and being completely honest, I'm more likely a consistent 1-1.25 moa shooter (even though I'd like to claim otherwise).