Is there any ballistics software out there that actually works?

Jon2

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Nov 28, 2005
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Location
UK.
Dear all

Just after some help.

After coming home after a couple of long range target practice days I have encountered seemingly, what are some big discrepancies betwen MOA calculations using Exbal and Sierra Infinity and what is actual MOA adjustment in the field. It prompted me to ask the question - is there any software that actually works out there?

Basically to explain the situation, I was shooting out to 600 yards. So before I went out, I ran the load I am using through Exbal to get a rough idea of the MOA correction I need to dial to get me on target.

Just to cut a long story short - every MOA figure according to Exbal was way out. For example it said at 550 yards I needed to come up 7.75 MOA. So I dial in 7.75, shoot 3 rounds and they are all way low. I ended up dialing in 9.50 to get on target. I was with a friend who uses Infinity so we run the figures through that and it says 8.0 MOA.

My point is that I have been in this situation before and I have had to put rounds on paper before I can confidently go out and hunt live game.

What should I be using (software wise) so I can confidently get accurate MOA adjustennt pre hunt? Does any such software exist?

Thankyou for any information/guidance to help get to where I want to be.
 
I've never had a single problem with Exbal. I had a good zero, based on a group that was less than .4" at 200yds with my 7mm Rem Mag. Exbal said 14.75moa to hit at 800yds. 3 shots later I had a 6" group at 800yds exactly centered on the target. Using Exbal only, I was on target from 200yds to nearly 1500yds with my 338AM. Same with my 300WSM etc.

I've found that with a good solid zero value and an accurate velocity, Exbal is very close.

What scope are you using? Have you verified it's clicks?

AJ
 
Just want to throw this in what did you confirm your yardage with ?? That could throw you off target.
 
AJ

I am using a 7mm Mag too. The scope is a NXS 3.5-15 x 50 which is virtually brand new. I have done a tracking test with this at 100 yards and it tracks perfectly.

Jeremy I am using a Lieca BRF pair of bino's to verify range.

The only thing I could possibly put it down to is sight height. I have input 1.5" from a previous similar set up but haven't actually checked this since. But I can't imagine that would make that much difference would it?
 
JON2 I HOPE YOU GET IT FIGURED OUT SOON, WHEN YOU DO LET US KNOW WHAT WAS WRONG. I JUST GOT THE NIGHTFORCE SOFTWARE FOR MY PPC HAVEN'T USED IT YET BECAUSE MY RIFLE IS AT THE SMITHS GETTING AN DEFENSIVE EDGE BRAKE INSTALLED . WHEN I READ YOUR POST IT MADE ME NERVOUS. WELL THEIRS SOME REAL SHARP GUYS ON THIS FORUM THEY SHOULD HELP YOU FIGURE IT OUT gun)
 
Jon2
Most likely it has to do with the input of info or wrong info entered.
The two programs were within a 1/4 MOA but you were off by 1-1/2 MOA at only 550 yards.
This leads me to think you are doing something wrong, Not the program.
Where did you get the velocity? did you input elevation, did you use standard PB? bullet BC?
maybe it was just bad luck and all little errors added up instead out canceling out.

Not pointing fingers, just telling as I see it.
Some input is not right. figure out whats wrong and you will be fine.
fudge some numbers if you have to, untill the numbers meet your actual drops.

Cam
 
You are making an assumption that your scope clicks are actually what they say. Big mistake. You need to check them first to determine actual click value.

Dan Lilja has got an article on his site about how to check that.

Second, are you putting in the correct air pressure and elevation or using the defaults.

BH
 
AJ

I am using a 7mm Mag too. The scope is a NXS 3.5-15 x 50 which is virtually brand new. I have done a tracking test with this at 100 yards and it tracks perfectly.

Jeremy I am using a Lieca BRF pair of bino's to verify range.

The only thing I could possibly put it down to is sight height. I have input 1.5" from a previous similar set up but haven't actually checked this since. But I can't imagine that would make that much difference would it?


With my Nightforce 3.5x15x50 on my 338AM, I use a 2.23" sight height. The sight height on my 7mmRM is 1.5", by using 2.23" on my 7RM data, it changes the Exbal 550yd estimate by 3/4MOA. That could be half the error you are seeing. If your velocity is off a little and your zero is off a little and the Baro pressure/Relative Humidity/temp are each off a little, that could be the other 3/4moa.

Tell us more about your load/velocity/bullet, sight in distance etc.

AJ
 
AJ.

2.23" scope height???

My 50 mm 1" tube ziess is 1.79" above bore. I couldn't get long range drops to match calc drops until I measured it accurately and enter the new number in the code. Looks like you're giving good council.

Maybe a new thread otta start here. How much line of site change between the 1" tube and 30mm tube. I'm trying to stay away from cheek piece. Or should I just calculate it?
 
Jon2
Most likely it has to do with the input of info or wrong info entered.
The two programs were within a 1/4 MOA but you were off by 1-1/2 MOA at only 550 yards.
This leads me to think you are doing something wrong, Not the program.
Where did you get the velocity? did you input elevation, did you use standard PB? bullet BC?
maybe it was just bad luck and all little errors added up instead out canceling out.

I agree.

I use Exbal with confidence for all my rifles.
Exbal or the other ballistic software programs are only as good as the info that you put into them.
You have a high quality scope and rangefinder.
A friend of mine had a similar experience to yours. He was shooting over a cheap chronograph. I verified his procedure, and it checked out. I had him shoot through my PVM-22 infrared chrono and his velocity was way off what he was originally putting in the program.
If you don't have access to one of the better chronographs, find a buddy with a similar one to yours and shoot over it and compare. You may be surprised with what you find.
 
Ballistic calculators these days are scary accurate. You put in good numbers, you get out good numbers.

You must input everything as accurately as possible. If ANY of the values below are not accurate even off by a little, can cause great missery.

Accurate velocity (corrected for the gap between chrony and rifle)

Real world drag function

Real world BC from two chronies or drop tests. Preferably both.

Accurate scope height

Accurate zero

Current temprature

Current raw barometric pressure at location regardless of altitude (make sure the ALT is set to 0') OR use actual altitude and set the pressure field to the pressure corrected at sea level found at the nearest airport.

Angle of fire (if greater or less than 0 degrees)

Current humidity (little consequence)
 
To be off that many clicks at 550 yards suggests to me that it isn't just one factor. Stated BC's for bullets are not always accurate. I often re-check my zero before shooting. Elevation and weather factors can move your poi by 1/4 inch or more at 100 yds. This can translate into big misses at longer distances. Add a few other small discrepancies in readings/input data and you may just have a plausible explanation for your prior experience.

I use exbal and found it to be very accurate for a drop tables with multiple calibers. What perplexes me is that it can be dead accurate for drop, but substantially off for windage. I can only assume operator error. Perhaps my wind meter is off???
 
Thanks everyone for your responses and help

This is where the internet excels I feel.

I am convinced now from the responses here that it has to do with the information I have input.

One main point I have picked up on is the fact that I have never paid any attention to altitude, baro pressure or any of these factors as I presumed (wrongly) that they didn't matter that much. Sounds like that is where I have made an error.

I am zero'd at 200 yards and load I am using is 7mm Rem Mag, 150 grn Nosler BT chrono'd @ 2980 (again here I just put in 3000 so that is also a mistake by the sounds of things). Sight height 1.5" again assumed (I think you can see a pattern forming here) and paid no attention to baro details altitude etc etc. I just wrongly assumed that those variables seemed too insignificant to make a difference but it sounds like I am wrong by reading all of your posts.

I am sure now that I need to go away and input more accurate data. I haven't got any type of device to measure the baro details etc so sounds like I need to invest in one.

Thanks again all for the advice it has been brilliant. I now know I need to get my act together more so with every single piece of inputted data.

Thanks again for all the info

Thanks for the offer Michael E will PM you my details
 
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