Need help understanding why my ballistics calculator is doing this!!

[Loner]

And I think it bares repeating, all the electronics we carry are all subject to loss, breakage and failure. Take written manual backups in the field. For years we've taped
drop charts to our stocks, now they put them inside the scope flip ups. Up here you can
about count on cold nasty weather screwing up your range finder at least once in a season. No point in having a nice mil or moa ranging reticle and not know how to use it
because you laid down on your iphone and cracked it to make the shot. I like smoa for
the simplicity of doing the math in my head. But I carry a game chart as well. My buddy
just took a nice 6x6 bull at 500. He missed the first shot because he never had done the
math on a trotting elk and lead. Fortunately the shot, 8 feet behind him, stopped him
and down he went with the second shot.
For us old guys remembering all this takes repeated drilling it in. That's what I'm doing
now I guess.

 

[CRNA]

Could you post up you complete data, it looks like FTE has JBM as a ballistics engine so I would use JBM online and help it to get squared away.

Copied from site, some of the answer may be in this. It may convert but not display the new number.

• Automatic Drag Model Conversions
  Automatically convert between two different drag models. Ballistic will recalculate the ballistic coefficient and adjust its trajectory to fit the new drag model. This is ideal if you only have a G1 coefficient for a VLD, spire point, or other type of uniquely-shaped projectile, as it allows you to apply a more accurate drag calculation. This may improve your long range accuracy beyond that of the standard G1 calculation provided by the manufacturer. Wish your manufacturer produced stepped BCs? Convert the drag model to apply a more suitable drag.

Well, the JBM calculator online will revert to the G7 profile. So, if I copied and pasted this data it would be data that was an incorrect dope for my rig. The way I got it to work in Ballistic was to use the G1 number and designate a G7 profile, which I know has to be wrong. I have checked and rechecked all of my atmospheric data and they were all correct.

Just a few more answers to questions that popped up throughout the thread:

My rig is a Savage with the Accustock and Accutrigger, McGowan SS match barrel in varmint contour (26"), Nightforce NXS 5.5-22X56 with Nightforce rings and base.

I know that 1100 yards is a loooong way. Would I even attempt to shoot an animal at that distance? No. This was more just for fun since the wind was fairly calm compared to most days at that shooting location. We usually shoot from 450yds-800yds. On light wind days it almost gets boring. There is no challenge to shooting 450yds. When we shoot at the silhouette torso targets at that distance, we are usually trying for headshots (about 4X5 inches). Would I shoot at an animal out to 700yds? You better believe it. The problem was just so pronounced at 1000-1120yds that it just didn't make sense. My shooting buddy hit the 1000+ target on the second try and then continued to ring it four more straight times with his .260. I fully expected the same results. In my opinion 4-5MOA error in elevation is massive. If I would have only shot a couple of times I would have chalked it up to updraft or something else, but this was repeatable for both distances. I shot twice at 1040 and my buddy said, "you are hitting near a patch of grass just above the target". I used my reticle to determine that I was about 5MOA off. I dialed down 5MOA and guess what.....HIT. Same thing happened with the farther target.

As I stated before, the only way I could possibly get the drops to come close to the actual POI was to either add 200FPS of MV, which is totally absurd. Or, to manipulate the BC numbers.

In short, I know that shot is difficult to make. I'm sure there are guys on here with tons more experience in long range shooting than me that could take me to school when it comes to slapping steel at that distance. It's just frustrating because in prior outings my ballistics calculator has been spot-on.

 

[Loner]

What engine are you set on? what was your
zero weather? what was your shooting weather? did you enter your shooting weather?
The calculator is not off. Your entry data is.

 

[Scot E]

CRNA,

Have you tested your scope clicks around the 25-30 MOA range you dialed to makes sure that you are still getting accurate and consistent clicks? I have seen some crazy things when a scope nears it limit of turret travel. It is logical to think the click value would decrease but I have seen it both ways.

I don't know how your scope is setup. Maybe you used a tapered base and nearing the turret max isn't the problem but it is sure something that I would test first thing.

I realize this doesn't adress your G1/G7 issue but at least it would eliminate some potential issues that could be causing your POI to be that high.

HTH,

Scot E.

 

[CRNA]

What engine are you set on? what was your
zero weather? what was your shooting weather? did you enter your shooting weather?
The calculator is not off. Your entry data is.

That's what's screwy. I have checked all that stuff. My zero weather, my shooting weather, everything. I agree with you that the calculator itself isn't off, I am. I just can't figure out what the heck happened.

 

[CRNA]

CRNA,

Have you tested your scope clicks around the 25-30 MOA range you dialed to makes sure that you are still getting accurate and consistent clicks? I have seen some crazy things when a scope nears it limit of turret travel. It is logical to think the click value would decrease but I have seen it both ways.

I don't know how your scope is setup. Maybe you used a tapered base and nearing the turret max isn't the problem but it is sure something that I would test first thing.

I realize this doesn't adress your G1/G7 issue but at least it would eliminate some potential issues that could be causing your POI to be that high.

HTH,

Scot E.

I have a 20MOA one-piece base and I have 100MOA internal clicks, so I am nowhere near my max turret travel. It is a good point that you bring up, but I just don't think it's the problem in my case. As I stated in my post above this one, I am sure it's user error, but man It's killing me cause I just can't figure out what it is.
I'm going to sleep on it another night before I set up an appointment with a shrink.

 

[bigngreen]

If you punch all your numbers into JBM does it match the data on FTE when you select G7?

 

[Loner]

Last try, what are your settings at? You haven't said a word about how you have your
program set up. A lot of the settings are in General settings, not in the program. A lot
of what you enter in a new favorite can't be altered later. Go through it and you may find you have simple turned on or variable bc off or atmosphere zero or current set different
than you need. Also if you are on a multi tasking ipod you have to kill the programs to
have new settings take.

 

[CRNA]

Yes. When I use JBM it will automatically revert to G7 and give the numbers using the BC of .316. On my ipod I can select the bullet, it gives the G1 BC, and then change to G7 profile but the number stays at .617 (the G1 BC) and the drops are right on with what I was shooting the other day.

 

[CRNA]

Last try, what are your settings at? You haven't said a word about how you have your
program set up. A lot of the settings are in General settings, not in the program. A lot
of what you enter in a new favorite can't be altered later. Go through it and you may find you have simple turned on or variable bc off or atmosphere zero or current set different
than you need. Also if you are on a multi tasking ipod you have to kill the programs to
have new settings take.

Loner,

I know what you are talking about. I don't think I have messed with anything in there on the settings page. I will take a look at that and report back. Thanks for bringing this up. To be honest, I totally forgot about going to the settings page and looking in there. You just might be on to something. Thanks!! I will let you know what I find when I have time to look at it.

 

[bigngreen]

Yes. When I use JBM it will automatically revert to G7 and give the numbers using the BC of .316. On my ipod I can select the bullet, it gives the G1 BC, and then change to G7 profile but the number stays at .617 (the G1 BC) and the drops are right on with what I was shooting the other day.

If yes, JBM and your I-pod software match when you choose G7 then your program is doing the change in the back ground but not displaying the change and your GTG if not then you keep digging. That's all I was getting at is checking it against a known software!

 

[CRNA]

If yes, JBM and your I-pod software match when you choose G7 then your program is doing the change in the back ground but not displaying the change and your GTG if not then you keep digging. That's all I was getting at is checking it against a known software!

Gotcha.

 

[Bart B]

I have seen some crazy things when a scope nears it limit of turret travel. It is logical to think the click value would decrease but I have seen it both ways.

It doesn't seem logical to me they'd change . Please explain how the click values would decrease.

And if by you having "seen it both ways," do you mean the click value increases? Please explain this, too.