Range Report ballistic cuves that dont "line up"???

[Ring]

useing shooter, but also have bulletflight and FTE

260, 142smk litz g7 scope is a razor

crono 2830fps

100y zero

DA 3000ft 85f


PC says 7.7 mils to 1k, DOPE was 6mils

if i reset chart to get 6mil, then speed is 3180fps,

now 600y is WAY off.. my 600y DOPE was 1.9mil
to get 1.9 @ 600, i would need a MV of 3509


and at 1750y, i was 22 mils, thats about 2935fps to do that...

 

[bohem]

Re: ballistic cuves that dont "line up"???

Double check your atmospheric inputs in Shooter, you should go into the settings on the very first screen (where you pick the firearm) and choose "Use Density Altitude" otherwise you're barking up the wrong tree.


From there double check all of your rifle inputs such as HoB but my initial suspicion is the Density Altitude checkbox. If you just input the altitude with the default settings you're not getting the inputs correct and you'll get total trash for output.

 

[Lowlight]

Re: ballistic cuves that dont "line up"???

None of that dope appears correct, I would check your yard lines at the range.

My 7WSM uses 3.2 Mils to 600 yards and 7.1 Mils to 1000, for your dope to be lining up, I would say you are shooting really, really fast or your scope is flat out wrong.

But I would almost question your ranges first, the scope second.

Those numbers are nothing near a 260 with 142s.

 

[Ring]

Re: ballistic cuves that dont "line up"???

ranges are right, this was at thunder valley, and i tested 3 guns, the 260 and a 243wssm and a 223...

shooter is set right, and i checked the data VS 3 other programs as well..

next step is checking the razor

but before the razor, i had a moa viper on it, and i had "simaler" numbers, but i need to go check my logbook to find that when i get home..

 

[Lowlight]

Re: ballistic cuves that dont "line up"???

You may think things are right but my 260 here in CO (5000+) at 80 degrees uses the following

600 yards, 3.3 mils
1000 yards 7.4 mils

That is with a 139gr going 2850fps so how are you 1/2 that drop at 600 yards and better than 1.4 mils to 1000 yards.

How you are going that much flatter does not add up by any means out there... it's so far off what a 260 should do, it begs the question.

Forget the computer, something is way off, if not the scopes, the ranges.

 

[bohem]

Re: ballistic cuves that dont "line up"???

Did you check your 100yd zero before you started?

I've seen really goofy data and the user chased his tail for 75 rounds trying to figure out why it was off by 1mil at 600yd, 1.1mil at 1000yd, and 1-ish mil at 1200yd.

Turns out his zero was 1 mil low at 100yd because he set the zero stop incorrectly.

 

[Ledzep]

Re: ballistic cuves that dont "line up"???

Yeah I would say check zero and scope in general. Run a box test and measure it to see if your clicks are true values.

 

[turbo54]

Re: ballistic cuves that dont "line up"???

You need to do a full-range tracking test. My Bender had me scratching my head for a year like this, before I did a trackng test and found it was magically advancing 2moa between 5moa and 10moa on the dial.

 

[Ring]

Re: ballistic cuves that dont "line up"???

hmmmm.... took it out the other day, marked 42" line on cardboard...

dialed 11.7 mills and hit the 42" line... so WTF!!!.. i was hoping it was going to be way off so i could have this fixed...

now what do i look at?

 

[Ring]

Re: ballistic cuves that dont "line up"???

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: turbo54</div><div class="ubbcode-body">You need to do a full-range tracking test. My Bender had me scratching my head for a year like this, before I did a trackng test and found it was magically advancing 2moa between 5moa and 10moa on the dial.</div></div>

hmmm... i think i make a chart with marks every 3.6" to 10 mils and try that

 

[Ring]

Re: ballistic cuves that dont "line up"???

ran test the other day, it "looks" like it might be a bit off, sending to vortex to check it out... and have them put in the 10mil HS knob as well

 

[CleanMoostang]

Re: ballistic cuves that dont "line up"???

One of my biggest problems not too long ago with doping my gun per shooter vs terminal ballistics was me using g7 drag model. switched it to g1 and my ballistics and actual range dope almost matched exactly..

 

[Augustus]

Re: ballistic cuves that dont "line up"???

Ring, what BC are you using and are you using G1 or G7.

 

[Ring]

Re: ballistic cuves that dont "line up"???

litz g7, but i dont think the g1 changes the numbers much...

i sent the razor in today to get looked at and while its in, get the new HS 10mil turrets put on...

 

[Augustus]

Re: ballistic cuves that dont "line up"???

What BC are you using

 

[Ring]

Re: ballistic cuves that dont "line up"???

142 6.5 smk
bc 0.301

 

[turbo54]

Re: ballistic cuves that dont "line up"???

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: CleanMoostang</div><div class="ubbcode-body">One of my biggest problems not too long ago with doping my gun per shooter vs terminal ballistics was me using g7 drag model. switched it to g1 and my ballistics and actual range dope almost matched exactly.. </div></div>

Not trying to start a G7 vs G1 argument.......

But I've also had better luck with G1. The logic behind G7 makes great sense. The data in Litz's book indicates G7 has way less variability over a wide range of velocities.

Nonetheless, whenever I try G7, the calculator predicts a very pessimistic trajectory, that is not able to be tweaked in with velocity alone.

I have absolutely tested my scopes full range, and have velocities from an Oehler 35P. G1 matches better for me.

 

[Augustus]

Re: ballistic cuves that dont "line up"???

I went back and re- read your post. If you are zeroed at 100 yds and your actual drop is 6 mils at 1000 yds, take Lowlights assessment as gospel. Your range is not accurate or the scope is screwed up.

 

[Ring]

Re: ballistic cuves that dont "line up"???

vrom Vortex today...

The tech found that the reticle was very slightly canted. He said that this could cause the tracking issues you were having. He has reset the reticle and will work on changing out the elevation turret today. He will thoroughly test everything to ensure that the scope is tracking properly before we ship it out tomorrow.

 

[Lowlight]

Re: ballistic cuves that dont "line up"???

I don't think a cant would cause that much deviation at 600 yards, you have a lot of difference here.

I would laser the ranges and double check everything as noted, your "actual" dope does not line up with a 260 forget the software part of it. And if the scope was only slightly canted, I am guessing if you didn't see it we are talking less than 3 degrees here. That is not gonna account for a full Mil or More at 600 yards. if you think about it you are better than 20+ inches off, that is huge. A slight cant isn't causing that much elevation to be off.

 

[Lucks]

Re: ballistic cuves that dont "line up"???

Just the other day my actual dope with 142's at 2810 fps with ~3000 DA was 8.2 mils at 1000y.

Like Lowlight said your scope is jacked up or you're shooting ~850y thinking its 1000y.

 

[Ring]

Re: ballistic cuves that dont "line up"???

 

[Lucks]

Re: ballistic cuves that dont "line up"???

Then it's your scope....

 

[MTyotehunter]

Re: ballistic cuves that dont "line up"???

I vote Scope problem...

 

[Ring]

Re: ballistic cuves that dont "line up"???

scope back from vortex, with the new 10mil turrets... so far looking good..

will be at the 1k range at the end of the month to fully test

 

[MitchAlsup]

Re: ballistic cuves that dont "line up"???

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Ring</div><div class="ubbcode-body">
PC says 7.7 mils to 1k, DOPE was 6mils
now 600y is WAY off.. my 600y DOPE was 1.9mil</div></div>

That 6 mills is probably 7 mills
That 1.9 mil is probably 2.9 mil
Then you are within the flight trajectories of the two gentlemen.