How to adjust b.c. to get ballistic chart to match drops

Lrreloader

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Yes. I show 2806 fps corrected. That is if the BC is right. Not that familiar with hammer but also at 600 and in BC doesn't have a large effect.

I used 1.87" scope height.
Scope height ended up being 1.834"
 

Lrreloader

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Soo... you guys are definetly above my level, thanks for keeping it simple BrentM. I have shot 1,000 yard comp and long range hunt with my father who has kills out to 1,860 yards.
We get close in height from basic charts off of berger website. But wind we usually call the shots left or right and "walk" it in because we usually shoot mountain to mountain with multiply gaps or ravines. I am going to read up on all the extra conditions
Why not read this before you do any more shooting!
If you do this you will pay for tge extra cost of the LabRADAR in ammo and your time; not to speak of your sanity.
ALso I would take your Lab RADAR along on the hunting trip!

shootski
Limited on gear backpacking on horses
 

Lrreloader

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Orkin I am definetly interest in aerodynamic jump as I have never heard of that will read up on that for sure
 

Lrreloader

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Ok so playing around with numbers on bergers ballistic program on their website.

If I adjust the b.c. .350 from manufacturer. 325 G7
Add correct scope height 1.834"
The hammer bullets are actually 263 grains
.338 diam
MV 2,780 fps ( that's consistent, charges measured out to .00 of a grain on lab scale)
1,400 elevation (where I shoot now)
59* temp when I shot drops

The drop shots was on a windy day flags were all directions all the way out to 1,000 so take that into consideration for actual clicks

200 yards is on
300 yard is 3.7 actual 3.50 moa clicks
600 yard is 12.01 actual 12.0

I think those values will be good enough to just change elevation to 9,500 and should be Minute of elk.

Range is expected to be less than 300 yards but gun has enough for farther and don't want to be held back by lack of a chart.

Sound good?
 

Teri Anne

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Hmmm….. I’m not sure what you have going on lol. I inputted a bunch of scenarios into my Shooter Application and nothing is adding up or coming close.

There is a big difference between shooting out to 500 yards vs. 1000. Out to around 500 is easily tweekable, but 1,000 you have to have very precise spot on info entered in to trig. out properly. Your best best is to buy a phone ap like Shooter Ballistics or Applied Ballistics and plug all the pertinent precise info in.

Barrel twist rate:
Twist direction:
Sight/scope height:
Sight offset:
Elevation units:
Turret Graduatons:
same as above for windage:
Elevation correction factor: (this can be used to tweek elev. or if scope doesn’t track perfectly to a 1.0:1.0 Moa ratio)
Bullet diam:
Bullet weight:
Bullet length:
MV:
Velocity variation and powder temp: (if you put in the time for variances)
Atmosphere std:
Drag Model G1/G7:
Zerod range:
Sighted in/Zeroed atmosphere:
Altitude:
Baro pressure: (best to use station pressure if you have a device that captures it, I.E. Range finder, Kestrel)
Temp:
Humidity:

Coriolis comes in to play a bit at 1,000 but the least of your worries now.

Then what you’re actual weather conditions/Atmosphere where you’re shooting at during said shooting session vs where you zeroed in at.

Going from 1,400’ to 9,500’ shooting at 1,000 yards, you’ll have to have most or all the above info to be accurate. A simple elevation change won’t cut it with what info you’re currently using.

Like I said I tried a bunch of tweaking and different scenarios and couldn’t really get close to what you’re actual is I tried scope height from about 1.6 to 2.1” (guessing), changed velocities by a couple hundred FPS, changed BC dramatically, changed scope elevation correction factors, tried to guess on your atmospheric conditions zeroed vs will be shooting at etc…. About the only thing I didn’t try was changing your zero yardage. I’m assuming you zeroed in at 100 yards? A lot of pertinent and necessary info missing to get it to all add up.
WOW!!! That seems like a lot of work to accomplish the same thing that you can simply do by going to the range and actually shooting the ammo that your rifle likes and noting the changes in elevation and windage, recording the data and then simply using the actual data for your first shot. I have never been able to get a ballistics chart to work accurately for me. Something is always going to change. Your elevation, temperature, barometric pressure, temperatures and the like are all variable, sometimes from stage to stage when shooting competition. Now lets throw in varying crosswinds, mirage as well as the much forgotten Coriolis and you have everything available to mess up your carefully planned ballistic data. Instead...for you long range hunters take what you have and make it work for you. If you know your rifle, you keep your ammo constant and take the time to get a base zero at the ranges you are going to shoot at, all you have to do is dial in the predetermined zero for the distance you are going to be shooting at, adjust for conditions and let the bullet fly down range. Experience says that while not always in the X ring or exact center of the boiler room of the animal you are shooting at but it will not be too far off and should result in a kill shot providing you did all of the other things you are supposed to do prior to shooting.

Hitting and not killing an animal does in fact induce a lot of pain and suffering. I was one of those animals twice in my military career and trust me getting shot is not a lot of fun even if non fatal. I was in fact thankful that the person shooting at me at the time simply got lucky by firing a lot of rounds (AK47 which I hate to this day) in my direction instead of being skillful and the round that connected while painful was only in the lower right flank and did not do a lot of damage.

Conversely what is it like when the bullet hits? Well stand in front of Milwaukee Brewers player Avisail Garcia and let him wind up and take his hardest swing with his bat and hit you anywhere in your body and you will have some idea of what it feels like when a .30 caliber bullet rips nto your body. Not a pleasant thought is it. You don't kill that deer, elk or other animal and you have just inflicted that amount of pain and subsequent suffering to them. Be an ethical hunter, as once supposedly said by Davey Crockett once upon a time, " Be sure you are right, then go ahead."
 

IHFarmer07

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Here’s something to read on also, I’m also refreshing my mind on this all to make sure I get it right….

I don’t do this on a daily. I have read/watched very experienced people’s written articles, forum threads/pinned threads, YouTube videos from @orkan, Erik Cortina, F-class John, Ryan from LRO. From most of them, they zero at 100, shoot at 600 and if things don’t line up they adjust velocity. From there they stretch it out to 800-1000 or however far you expect to shoot to and they adjust the bc to get poi corrected because of the loss of speed makes the bc of the bullet change.
Do I have this procedure/process correct?
 

dfanonymous

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Here’s something to read on also, I’m also refreshing my mind on this all to make sure I get it right….

I don’t do this on a daily. I have read/watched very experienced people’s written articles, forum threads/pinned threads, YouTube videos from @orkan, Erik Cortina, F-class John, Ryan from LRO. From most of them, they zero at 100, shoot at 600 and if things don’t line up they adjust velocity. From there they stretch it out to 800-1000 or however far you expect to shoot to and they adjust the bc to get poi corrected because of the loss of speed makes the bc of the bullet change.
Do I have this procedure/process correct?
Yes, you are correct more or less the small details. Don’t try too hard to convince anyone.

There are 100s of threads on here where this is spelled out and still these questions pop every week with wild opinions and over simplifications or just straight up incorrect information.

Best anyone can do is put the information out there, and maybe a person is smart enough to recognize good information to further verify.
 

AC300Win

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No expert, but similar experience with a 300 win and 200 grain eldx. Research the use of two entries for the drag model. First entry g7 BC with zero velocity and second entry with a lower BC with an estimated downrange velocity. Requires verification but seems to work pretty well. Can’t remember where I picked that tip up but maybe someone with more knowledge on the subject can chime in. Btw using the shooter program.
 

BFD Guns

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Wouldn't one have to zero at the new elevation or weather for the rest of the projected dope from the ballistic applications to be accurate?
 

Alex Wheeler

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I do it the easy way. Zero at 1000 yards on a dead calm day. Then adjust my turret to what the data says the drop should be. Works every time. I dont worry about spin drift or tweaking number to fit. This assumes I have an accurate BC number like on a Berger. My 100 yd zero will be off a little but I dont care. I would not do this method for elr stuff, but it will be solid from 1k and in.
 

BFD Guns

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Not really, no. That’s why we use 100yd zero.
That's assuming the gun is zeroed at 100. Once that is established all the rest of the data should fall in line, but if I have a 500ft elevation 80 F. confirmed zero then go to 9000 ft elevation and 30 F how do I know where to set my zero if I don't actually shoot it.
 

IHFarmer07

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I do it the easy way. Zero at 1000 yards on a dead calm day. Then adjust my turret to what the data says the drop should be. Works every time. I dont worry about spin drift or tweaking number to fit. This assumes I have an accurate BC number like on a Berger. My 100 yd zero will be off a little but I dont care. I would not do this method for elr stuff, but it will be solid from 1k and in.
Hmm, that’s a cool/unique way of doing things, interesting.
 

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