Why don't my Ballistics Work?
- Thread starter ghorsley
- Start date
Re: Why don't my Ballistics Work?
what conditions are you inputing? And what load are you shooting ect.
what conditions are you inputing? And what load are you shooting ect.
Re: Why don't my Ballistics Work?
Well I don't have the program open but I followed all the inputs that NF said to put in. Plus I printed another posters input data for the FTE and did what he said.
I shoot 175 FGMM and 175 SMK from Southwest.
There was very little wind when I shot 300/500 this morning.
Well I don't have the program open but I followed all the inputs that NF said to put in. Plus I printed another posters input data for the FTE and did what he said.
I shoot 175 FGMM and 175 SMK from Southwest.
There was very little wind when I shot 300/500 this morning.
Re: Why don't my Ballistics Work?
Do you have a verified velocity(from your rifle) for both of these rounds? What bc are you entering for the 175s? How far off is your ballistic solution? Can you say that you are competent at these ranges enough to eliminate that variable? Have you tested the tracking on your scope? Some of these variables can influence your solutions accuracy.
Do you have a verified velocity(from your rifle) for both of these rounds? What bc are you entering for the 175s? How far off is your ballistic solution? Can you say that you are competent at these ranges enough to eliminate that variable? Have you tested the tracking on your scope? Some of these variables can influence your solutions accuracy.
Re: Why don't my Ballistics Work?
If you don't know the velocity of the ammo, from YOUR rifle, it won't be spot on. If you don't know the environmental conditions (density altitude, temperature, humidity, etc) where YOU are shooting from, it won't be spot on.
Lastly, every rifle shoots a little different, even if you do know all of the above, it may still not be spot on.
Ballistic calculators are to help get you close, nothing is 100% except data you have from a previous shot in the same conditions. Hence the expression: DOPE
(D)ata
(O)n
(P)revious
(E)engagements
If you don't have a log book, purchase one and start recording conditions, ranges, and your scope settings on your shots. Next time around you will have solid info for a shot that will, under the same conditions, be spot on.
Rich
If you don't know the velocity of the ammo, from YOUR rifle, it won't be spot on. If you don't know the environmental conditions (density altitude, temperature, humidity, etc) where YOU are shooting from, it won't be spot on.
Lastly, every rifle shoots a little different, even if you do know all of the above, it may still not be spot on.
Ballistic calculators are to help get you close, nothing is 100% except data you have from a previous shot in the same conditions. Hence the expression: DOPE
(D)ata
(O)n
(P)revious
(E)engagements
If you don't have a log book, purchase one and start recording conditions, ranges, and your scope settings on your shots. Next time around you will have solid info for a shot that will, under the same conditions, be spot on.
Rich
Re: Why don't my Ballistics Work?
RTHUR and LAWNM, Thanks for the replies.
I know that one round is 2620.
As to the stuff about atmospheric conditions, on the FTE you can query for the local details and temp etc will change. Which I did today.
The DOPE is something I just started this morning. Guess I was looking for the easy way.....too many variables for me to rely on the calculators going forward. (although IMHO, if the inputs are correct they should do more than get you on paper)
I learned something today....many thanks
RTHUR and LAWNM, Thanks for the replies.
I know that one round is 2620.
As to the stuff about atmospheric conditions, on the FTE you can query for the local details and temp etc will change. Which I did today.
The DOPE is something I just started this morning. Guess I was looking for the easy way.....too many variables for me to rely on the calculators going forward. (although IMHO, if the inputs are correct they should do more than get you on paper)
I learned something today....many thanks
Re: Why don't my Ballistics Work?
MrHiggins,
Once you get used to your app you should be able to fine tune it with your inputs to give good results.The quality of your inputs will reflect the quality of your results.
MrHiggins,
Once you get used to your app you should be able to fine tune it with your inputs to give good results.The quality of your inputs will reflect the quality of your results.
Re: Why don't my Ballistics Work?
I am using bullet flight on my iPhone and it's pretty damn close as long as all the information is correct. The best information is that from ore Iliad range trips though as suggested with DOPE.
I am using bullet flight on my iPhone and it's pretty damn close as long as all the information is correct. The best information is that from ore Iliad range trips though as suggested with DOPE.
Re: Why don't my Ballistics Work?
What you need...
<span style="font-weight: bold">Accurate muzzle velocity of your load.</span>
<span style="font-weight: bold">Measured distance of 100yds to:</span>
1)Shoot and establish a precise 100yd zero.
2)Dial up from zero to 30 moa. Shoot a 3 shot group (still at 100yds). The distance between your zero and 30 moa up should be a measured 31.41". If it is not you need to establish a correction factor for your sights. Even though sights say 1/4 moa adjustments they are almost all off. Nightforce has an area where you can enter your 'true' click value (i.e. .23 moa).
<span style="font-weight: bold">Record your 100yd zero atmospheric data in the NF Exbal and 'save'.</span>
Exbal has the factory load data in it for Federal GMM. I would use that as a good base line. I would also enter in Sierra's multiple G1 BC's to more accurately match the drag profile of the SMK, its closer to a G7 profile (not availlable in Exbal). Multiple G1's will be more accurate than doing only one G1 bc which is only an average bc. If you look up "Bullet Data" in Exbal it will give you the multiple BC's for the different velocity ranges for that bullet. Just click "Enable Multiple BC's".
<span style="font-weight: bold">Next you can test it in field conditions</span>.
I prefer to use Station Pressure which is the pressure at where you are shooting (i.e. 27.55hg). Ignore the altitude (leave zero) as that is only going to reference what the pressure should be at that given altitude instead of what it actually is.
Make sure you enter the cosine if there is any when you shoot. <span style="font-style: italic">Ballistic software is a composition of math formula's, they are only going to be as accurate as the data <span style="text-decoration: underline">you</span> supply.</span> Now you can test it and if it is off it is usually because there is some margin of error in the cronographs. Simply do a "Trajectory Validation" in the program and Exbal will auto adjust the velocity to match your trajectory.
If this fails you can pm me with your phone number and i would be happy to help you walk through the process. Good Luck!
What you need...
<span style="font-weight: bold">Accurate muzzle velocity of your load.</span>
<span style="font-weight: bold">Measured distance of 100yds to:</span>
1)Shoot and establish a precise 100yd zero.
2)Dial up from zero to 30 moa. Shoot a 3 shot group (still at 100yds). The distance between your zero and 30 moa up should be a measured 31.41". If it is not you need to establish a correction factor for your sights. Even though sights say 1/4 moa adjustments they are almost all off. Nightforce has an area where you can enter your 'true' click value (i.e. .23 moa).
<span style="font-weight: bold">Record your 100yd zero atmospheric data in the NF Exbal and 'save'.</span>
Exbal has the factory load data in it for Federal GMM. I would use that as a good base line. I would also enter in Sierra's multiple G1 BC's to more accurately match the drag profile of the SMK, its closer to a G7 profile (not availlable in Exbal). Multiple G1's will be more accurate than doing only one G1 bc which is only an average bc. If you look up "Bullet Data" in Exbal it will give you the multiple BC's for the different velocity ranges for that bullet. Just click "Enable Multiple BC's".
<span style="font-weight: bold">Next you can test it in field conditions</span>.
I prefer to use Station Pressure which is the pressure at where you are shooting (i.e. 27.55hg). Ignore the altitude (leave zero) as that is only going to reference what the pressure should be at that given altitude instead of what it actually is.
Make sure you enter the cosine if there is any when you shoot. <span style="font-style: italic">Ballistic software is a composition of math formula's, they are only going to be as accurate as the data <span style="text-decoration: underline">you</span> supply.</span> Now you can test it and if it is off it is usually because there is some margin of error in the cronographs. Simply do a "Trajectory Validation" in the program and Exbal will auto adjust the velocity to match your trajectory.
If this fails you can pm me with your phone number and i would be happy to help you walk through the process. Good Luck!
Re: Why don't my Ballistics Work?
Calibrating software is a multi-step process that requires the best possible real time information the shooter can muster.
The shooter needs to
1. Accurately calibrate their scope. You must verify its tracking and adjustments across the entire range of movement. ( you'd be surprised)
2. You need to chronograph your load
3. Verify your actual drop at distance, to include out to 800 yards with most 308 loads.
Once this is done and combined with accurate weather data you can then adjust the software to match your system.
Shooting the ELR Course at Gunsite this week we spent a full day calibrating our software. This gave me accuracy to within .1mils out to 2100 yards on unknown distance targets.
There are no free rides,
Calibrating software is a multi-step process that requires the best possible real time information the shooter can muster.
The shooter needs to
1. Accurately calibrate their scope. You must verify its tracking and adjustments across the entire range of movement. ( you'd be surprised)
2. You need to chronograph your load
3. Verify your actual drop at distance, to include out to 800 yards with most 308 loads.
Once this is done and combined with accurate weather data you can then adjust the software to match your system.
Shooting the ELR Course at Gunsite this week we spent a full day calibrating our software. This gave me accuracy to within .1mils out to 2100 yards on unknown distance targets.
There are no free rides,
Re: Why don't my Ballistics Work?
Wish I had been better at math in school. It has come back to bite me and I am always trying to find a work around.
I really need to go to a precision rifle school that will make sure I understand how to put all this together before moving me forward. Any suggestions.....I am in Atanta.
Wish I had been better at math in school. It has come back to bite me and I am always trying to find a work around.
I really need to go to a precision rifle school that will make sure I understand how to put all this together before moving me forward. Any suggestions.....I am in Atanta.
Re: Why don't my Ballistics Work?
I think that is a great idea, the rifle school. Although my data is working good for me where I shoot I am in need of a few classes too. Good luck.
I think that is a great idea, the rifle school. Although my data is working good for me where I shoot I am in need of a few classes too. Good luck.
Re: Why don't my Ballistics Work?
Head west toward Kingsville,Tx. It is called Rifles Only, PR1&2.
Head west toward Kingsville,Tx. It is called Rifles Only, PR1&2.
