Ballistics Calculations???

[CouesN4Abruisin]

I'm new to the dialing shooting, but I have a pretty good setup.  I am shooting a Christensen Arms Mesa Bronze in 6.5 Creedmoor and for the Optic I am using a Leupold VX3i 8.5x25x50mm LRP in 1/4 in MOA Sight Height 1.88 inches, barrel is 1/8 twist and 22 inch with muzzle break.  I zeroed my scope with some factory ammo at 100 yards.  The rounds I used were Remington Core-Lokt 140 grain box says BC 0.410 Velocity 2700.  I plugged that data into Hornady Ballistic Calculator and got something totally different than what I'm having to adjust.  I then picked up some factory Hornady BTHP 140 grain box says BC 0.580 Velocity 2690.  I plugged that data into Hornady Ballistic Calculator and got something totally different than what I'm having to adjust.  So I picked up a Chronograph and shot through it to see if Velocities were off. Core-Lokt's average was like 2740 but they bounced from like 2800's to low 2600's.  Hornady's average was like 2650 but they stayed between 2700's to 2600's.  Anyway plugged in what I got still it wasn't what I'm shooting. 

So here is my data (actual rounds going down range to produce this) ...

Remington Core-Lokt 140 grain                                                                  Hornady BTHP 140 grain

Distance     MOA      Windage                                                                         Distance     MOA     Windage

100              Zero                0                                                                              100              Zero                0

200              3 in                  0                                                                              200             1.5 in               0             

300              6.5 in              0                                                                              300              5 in                  0             

400              9.5                   1R                                                                           400              8 in                  1R

500               13                   3.5R                                                                        500              11.5                3.5R

Hornady Calculator Data below (a few on paper and a few misses) ...

Remington Core-Lokt 140 grain                                                                  Hornady BTHP 140 grain

Distance     MOA      Windage                                                                      Distance     MOA     Windage

100               Zero                0                                                                             100              Zero               0

200              1.7 in              0                                                                              200              1.8 in              0             

300              4.4in               0                                                                              300              4.4 in              0             

400              7.5                   1R                                                                           400              7.4 in              1R

500              11.2                 3.5R                                                                        500              10.7                3.5R

So my question is am I doing something wrong? I am new to all of this and I know that everyone says that reloading is the way to go, but this is what I have for right now.  So any insight on if I'm missing something on the Ballistics Calculator or at the range? Thanks 

[maximus]

http://appliedballisticsllc.com/ballistics/

try this one.

[MTNSGT]

I use strelok and it is very close to actual. I dont have a chrono so I had to do some trajectory validation to find a close velocity that I believe is about spot on. I have found that the Hornady app is about 1 MOA off in some cases compared to strelok, shooter, applied ballistics, and the G7 ballistics calculator. Once I found my "actual" velocity, I compared all of the above mentioned calculators. The closest to center on paper at 300 yards was strelok. All were tested with the same ammo at the same distance allowing cooling time between each group. I've read that the more precise your inputs are the better outputs you will get. I havent had the chance to really stretch it out and see how accurate the outputs I'm getting are but 1st round hits at 600 are pretty good in my eyes. Especially have zero long range shooting experience prior to.

[10Turkeys]

The 3 biggest lies in the outdoor world are temp ratings on a sleeping bag, person rating on tent size, and the velocity on a box of factory ammo.

[Big Browns]

In order to get the best info you ALWAYS  have to adjust your velocity to match the real world range validation.  The velocity on the box and the initial range inputs on ballistic apps are almost always wrong.  That's why it imperative you validate your real world data and adjust your program to match!

[CouesN4Abruisin]

Some more of what I did... I took about ten shots and averaged them to get the velocity and the range, I use my actual range finder to determine distance.  I shoot at the range and also real world scenarios in the desert to try to get the best out of my shooting abilities.  I do realize that the ranges on the box and velocities are not going to match my rifle.  So I've done what I can to get as pin point as possible with what I know so far.  I appreciate all the positive feedback everyone has provided and will definitely look into these apps!!

[Zeke-BE]

4 hours ago, Big Browns said:

In order to get the best info you ALWAYS  have to adjust your velocity to match the real world range validation.  The velocity on the box and the initial range inputs on ballistic apps are almost always wrong.  That's why it imperative you validate your real world data and adjust your program to match!

And this is why no body really can just buy a rifle and some factory rounds type it in their calculator and hope to hit their 700 yard target

[recurveman]

Just for reference.   If my ammo velocity was off from shot to shot more than 20 FPS I might just throw the ammo away and start over.   If you want to shoot past 400 yards your ammo velocity needs to be MUCH closer from shot to shot than 100 FPS.   That is absolutely a horrible speed spread.    If you can get the speed difference to single digits even better.  

Remember the charts are only as good as the info you put into the charts.   If you chrono reads a different than actual speed (I've seen multiple choro's be 50+FPS different than another chrono on the same day) then the info is wrong.   One of the biggest influences on a change in point of impact that I have seen is a change in elevation.   If your elevation is off by a few thousand feet then your point of impact and your dope will be off.   

At one time I shot a buddies rifle for him and determined his drops.   I sighted in at 200 yards and then dropped back to 400 and then 600 yards to see how much drop the load actually was going to show.   Once I knew the drop in inches I could figure out what yardages his BDC's were at in his scope.   Quite a bit different than advertised.   Always verify and if the chart doesn't match reality then throw the chart away and use the drops you actually had in the field.   

[rcdinaz]

you are not that far off considering the mfg probably uses a different length barrel, calculates in ideal conditions, G1 vs G7, where your chrony was for MV measurements, etc.  

You can play with the MV and see if you get something close or do the actual changes if you have software that will accept multiple inputs.  It is probably easier to find a YouTube video to see how to work with your software than to have everyone try to explain it in writing.

 

[SHOOTER]

Don't pay much attention to the velocity on the box or the chrono ...the chrono is a good starting point and good to make sure you have low ES. Reloading i try to keep mine below 10fps.

Even the better ballistic apps need some fine tuning to get the drops right. Go out and validate the drop with your rifle at extended range (the further the better) and mess with the app till the drop calculator match what your actually seeing in the field... also I could never get the cheap apps to do this much past 600yards. I would go with applied ballistics or bullet flight they have been way easier to tune to my rifle/loads and way more accurate than any other apps.

You have to know how your rifle shoots. I've never been abe to plug in the speed off the chrono and the conditions and been able to hit what I was aiming at past 600- 700yards. It all takes alot of shooting and recording to get it all to line up. Once you do tho it's cool to see how well you can range dial and shoot and hit. 

[Cell4soul]

Time to start reloading.  Your velocity spread is huge with either of those factory ammo and the further you shoot the more it will affect you. 

[AZAV8ER]

use Ballistic APP and a Density Altitude APP

[recurveman]

11 hours ago, SHOOTER said:

Don't pay much attention to the velocity on the box or the chrono ...the chrono is a good starting point and good to make sure you have low ES. Reloading i try to keep mine below 10fps.

Even the better ballistic apps need some fine tuning to get the drops right. Go out and validate the drop with your rifle at extended range (the further the better) and mess with the app till the drop calculator match what your actually seeing in the field... also I could never get the cheap apps to do this much past 600yards. I would go with applied ballistics or bullet flight they have been way easier to tune to my rifle/loads and way more accurate than any other apps.

You have to know how your rifle shoots. I've never been abe to plug in the speed off the chrono and the conditions and been able to hit what I was aiming at past 600- 700yards. It all takes alot of shooting and recording to get it all to line up. Once you do tho it's cool to see how well you can range dial and shoot and hit. 

This info above is very spot on.   I would follow his advice very closely.   

[CouesN4Abruisin]

Thanks for all the positive input that I have received.  I tried the applied ballistics site and it was the closest to what I had shot real world.  However for my hunt I used my data I had already collected.  I went ahead and hunted with the Hornady rounds instead of the Remmington because of the accuracy and shot groups at further distances.  I was able to shoot at 400 yards uphill with one shot, this may not be long range to a lot of you fellow hunters/shooters, but that was far for me.  I have never shot a deer past 150 yards so I was pumped and looking forward to trying some target practice out to some further distances to test the limits of this rifle!  Thanks again!

[AZAV8ER]

3 hours ago, CouesN4Abruisin said:

Thanks for all the positive input that I have received.  I tried the applied ballistics site and it was the closest to what I had shot real world.  However for my hunt I used my data I had already collected.  I went ahead and hunted with the Hornady rounds instead of the Remmington because of the accuracy and shot groups at further distances.  I was able to shoot at 400 yards uphill with one shot, this may not be long range to a lot of you fellow hunters/shooters, but that was far for me.  I have never shot a deer past 150 yards so I was pumped and looking forward to trying some target practice out to some further distances to test the limits of this rifle!  Thanks again!

Great shot given what sounds like limited experience. 400 yards is a respectable distance in the field. I have had good groups with Hornady Precision Hunter ammo out of 2 6.5C's and a 270 WIN. Congrats.