ballistic phone apps for an android phone

[peterozrover]

Good Morning All,
First time poster, lifetime shooter here. I would like advice about any Android phone apps that I can use to dial in my caliber and the weight of my bullet that can tell me at what initial range my chosen load will first cross my line of sight as it rises on it's ballistic path and then falls after hitting the top of it's ballistic path: ie; in the name of conserving ammunition on initial sight in, at what distance will the projectile from my .30/30, .270, .308 etc. first cross the line of sight before hitting it again at my chosen zero, whether it is 100, 200, or 300 yards? The answer will probably lie within 25 to 40 yards but an app to determine that distance would be most helpful. Thank you in advance.
peterozrover

[JohnV]

You are going need the muzzle velocity and the BC of the bullet .
I don't now about android . This is a very good online database of Ballistic programs I use myself . Written by James Brad Millard .
https://jbmballistics.com/ballistics/ca ... tors.shtml for PC . If you go to the software page there is a few extra free calculators. In the big scheme of things where the bullet lands on the target at your chosen zero range is more important . Once you get it sighted in move the target closer until it hits where you aim . If android has Ballistic AE that's not a bad program but just make sure the windage corrections go the correct way as that is a common mistake in ballistic software .
With the JBM basic program If you set the range increments to 5 meters with your normal zero and other data in it , then it will show how far under it is at the shorter ranges and when it flattens out to the zero .

[bladeracer]

Good Morning All,
First time poster, lifetime shooter here. I would like advice about any Android phone apps that I can use to dial in my caliber and the weight of my bullet that can tell me at what initial range my chosen load will first cross my line of sight as it rises on it's ballistic path and then falls after hitting the top of it's ballistic path: ie; in the name of conserving ammunition on initial sight in, at what distance will the projectile from my .30/30, .270, .308 etc. first cross the line of sight before hitting it again at my chosen zero, whether it is 100, 200, or 300 yards? The answer will probably lie within 25 to 40 yards but an app to determine that distance would be most helpful. Thank you in advance.
peterozrover

I've never heard of such an app as every firearm/ammo/sight combination is different. I think most firearms are set up to have the bore axis and sight axis converge out at some distance rather than be parallel, without some convergence your bullet will never cross your line of sight at any distance. For accuracy you would use a chronograph to measure your muzzle velocity but it is not essential.

You could try a laser but they're no more precise than bore sighting.

The simplest way is to bore sight the rifle by looking through the bore at a sheet of paper at 50m and adjusting the sights to the same place, then fire at least one round and make a final correction, plus a second round to confirm. If the rifle is less accurate, like an open-sighted lever-action, then you'll want to fire groups so you can determine the mean centre of the group.

I use this when playing with external ballistics. It's not an app but it runs on a phone as long as you have an internet connection, just screenshot the data for future reference.
https://shooterscalculator.com/ballistic-trajectory-chart.php?pl=%5BPreset+Name%5D&presets=&df=G1&bc=0.135&bw=40&vi=1070&zr=110&sh=3.145&sa=0&ws=10&wa=90&ssb=on&cr=550&ss=1&chartColumns=Range~m%60Elevation~cm%60Elevation~MOA~FBFFF5%60Windage~cm%60Windage~MOA~FBFFF5%60Time~s%60Energy~ft.lbf%60Vel%5Bx%2By%5D~ft%2Fs&lbl=&submitst=+Create+Graph+

[JohnV]

Normal parallel scope mounts are just that parallel. The erector tube within the scope moves the image up and down side to side , it distorts where you see the image in relation to the target . That gives the ability to sight in to a certain impact point within the scopes adjustment range but it's better for the erector tube to be fairly close to the middle of the tube body or objective lens when sighted in . Hence there is 10 , 15 , 20 ,30 and 40 MOA canted rails to help achieve that at longer ranges .
I agree with Blade bore sight it first at 50 meters , get the bore centered on the bullseye get the cross hairs right on the center of the target then move to 100 meters and get it lined up left to right and grouping where you want on or slightly above the bullseye . Don't try to sight in on a brisk windy day . If you are intending to zero out further then calculating the drop would be helpful at longer ranges to at least get on the target . Once you go over about 300 meters the scope really needs external target turrets so you can keep your 100 meter zero on the turrets at 0 mark and then just click any extra holdovers on the elevation turret . A Mil hash or dot reticle is nice because any windage hold off can be done on the reticle .

[on_one_wheel]

Strelok Pro works extremely well.
It will do what your looking for plus much much more provided the data you enter is accurate.

[Wyliecoyote]

Strelok Pro works extremely well.
It will do what your looking for plus much much more provided the data you enter is accurate.

Exactly what I was going to suggest. But there is a problem, Strelok has been removed since the Ukraine war. I know that sounds dumb but that is what they say. It would have all the relevant data and then some that the OP was asking for. I know of no other app that does so.

https://www.recoilweb.com/united-states ... 78993.html

[JohnV]

If you can't find an app for the android phone then that is not really a problem just do the work you need on your computer .
Every ballistic program that can take range increments of 5 meters will show the trajectory from 0 meters to whatever .
You just have to find out the Muzzle velocity and the bullets BC and what drag function the BC is , like G1 or G7 whatever .
If you can't get any BC data on the bullet then as I said above it is possible to model your own bullet in JBM Point Mass from measurements but it is difficult . Another half baked way is compare your bullet to another commercial bullet with a known BC .
Look here there might be something that helps https://worldsapps.com/download-strelok-pro
I can't use strelok because of the different coloured texts some I just can't see and on a phone even more difficult . JBM is just as good as anything else . If your aim is a portable calculator to take into the field or on the range then you need an app.
I used Ballistic AE in an Ipod Touch fro some time in the field but I gave that up too much time wasted and the game moves and you loose the shot . I changed to just using a range card and a range finder .

[on_one_wheel]

Strelok Pro works extremely well.
It will do what your looking for plus much much more provided the data you enter is accurate.

Exactly what I was going to suggest. But there is a problem, Strelok has been removed since the Ukraine war. I know that sounds dumb but that is what they say. It would have all the relevant data and then some that the OP was asking for. I know of no other app that does so.

https://www.recoilweb.com/united-states ... 78993.html

Interesting, luckily it's still working on my phone, but it's definitely not showing up on the play store.

My next go to ballistic app would be Applied Ballistics,
I have the book and software for my pc and I see they have an app now.
If it's anything like the book and software, it'll be as pretty awesome.

[JohnV]

I think Applied Ballistics is by Brian Litz re Berger so it should be good especially for longer range bullets G7 drag stuff which litz did a lot of BC testing and adjusted some commercial bullet BC's to be more accurate . However NO single BC can predict a full trajectory perfectly from start to finish . It takes a range of BC's in velocity steps along the trajectory path to get very close ..

[Wyliecoyote]

John i agree with you about using the app on a device in the field. With Strelok i calculated my drop then printed out a range card incremented in 25 yards from 0 to 800 yards along with a 5 mph windage value. I reduced its size and laminated it and it goes with the rifle and in some instances attached it to the buttstock for quick access.
New generation range finders should have the ability to load and store this information in a more advanced way that current generation Leopold TBR range finders do with limited standard cartridge information. Burris does it with their digital scopes so it should be expanded more broadly to a handheld range finder.

[on_one_wheel]

. However NO single BC can predict a full trajectory from start to finish . It takes a range of BC's in velocity steps along the trajectory path .

I'm not exactly sure what you mean,
Do you mean from zero metres to whatever with every meter calculated in-between like this ?

Screenshot_20231022-091004_Strelok Pro.jpg (295.97 KiB) Viewed 1237 times

[JohnV]

John i agree with you about using the app on a device in the field. With Strelok i calculated my drop then printed out a range card incremented in 25 yards from 0 to 800 yards along with a 5 mph windage value. I reduced its size and laminated it and it goes with the rifle and in some instances attached it to the buttstock for quick access.
New generation range finders should have the ability to load and store this information in a more advanced way that current generation Leopold TBR range finders do with limited standard cartridge information. Burris does it with their digital scopes so it should be expanded more broadly to a handheld range finder.

Yes mate smart move , once you do a bit of that type of shooting you soon see the limitations of too much technology and too much wasted time . I only had an older model range finder it has no memory . That's why Military snipers have an offsider to handle all the calculations and target identification etc. and feeds that info to the trigger man so he can concentrate on the target in the scope and just move his turrets when required . A single shooter doing it all and fiddling with a ballistic app is too stressful and it can screw up the shot .

[JohnV]

Double post

[JohnV]

. However NO single BC can predict a full trajectory from start to finish . It takes a range of BC's in velocity steps along the trajectory path .

I'm not exactly sure what you mean,
Do you mean from zero metres to whatever with every meter calculated in-between like this ?

Screenshot_20231022-091004_Strelok Pro.jpg

My comment about the range increments was to address the original OP's need to see his close range trajectory data of where the bullet starts to cross the line of sight . I suggested 5 meter increments in a ballistic program or app but 1 meter if it's possible would also work but you must give a far zero like 100 meters to see the negative drops from the muzzle to the zero and where it starts to flatten out .
The comment you linked to has nothing to do with that .
Most ballistic programs and apps only ask for one BC entry and one single BC at one single velocity boundary can not predict a trajectory that well . It's close but if a program can except 3 BC's and the velocities they occur at then that will give a better firing solution . When commercial bullet makers quote a BC on the bullet box or website it is usually the largest BC figure in a string of calculated BC's at different velocities . The largest number is more impressive for sales reasons . Some will quote an average for that string of BC's and that is a bit more real . Some will quote a G1 BC because the number is bigger and more impressive when the bullet is in fact a G5 or G7 drag function that gives a lower number on calculation but will in fact be more accurate in a program because the correct drag function for the bullet is being used .
If you model a bullet in JBM Point Mass program and select include BC's you will see the print out of all the BC's along the trajectory path . Real Military snipers use multiple BC's in firing solutions but they don't tell anyone .
I hope that clears it up I don't know what else to say let me know if it don't and I will try again a different way . Some ballistic programs have a custom BC function entry that usually allows multiple BC's and velocity boundaries to be entered but sometimes they only accept a single velocity entry not a high and low velocity so just pick the velocity in the middle of the high and low that is quoted .
If you go on the Sierra bullet site some target and longer range bullets have 3 BC's and velocities stated .
As an example this is for the Sierra 168 grain HPBT Match bullet :--- .462 BC @ 2600 fps and above .447 between 2600 and 2100 fps .424 between 2100 and 1600 fps .405 @ 1600 fps and below . However the retards don't state the drag function which I am assuming by the large numbers is a G1 but in fact that bullet would be a G7 but it gives you the idea . anyway

[on_one_wheel]

Now I've got you John, I wrongly assumed that the apps would allow for BC changes as the velocity reduces.
I've got an opinion to enter 5 different bc values at various speeds throughout the flight path all be it not a true sliding scale

[Oldbloke]

Good Morning All,
First time poster, lifetime shooter here. I would like advice about any Android phone apps that I can use to dial in my caliber and the weight of my bullet that can tell me at what initial range my chosen load will first cross my line of sight as it rises on it's ballistic path and then falls after hitting the top of it's ballistic path: ie; in the name of conserving ammunition on initial sight in, at what distance will the projectile from my .30/30, .270, .308 etc. first cross the line of sight before hitting it again at my chosen zero, whether it is 100, 200, or 300 yards? The answer will probably lie within 25 to 40 yards but an app to determine that distance would be most helpful. Thank you in advance.
peterozrover

Sounds to me all you want is path of trajectory for sighting in?

Try here:

https://www.hornady.com/team-hornady/ba ... lators/#!/
Web site, not an app.

[JohnV]

Now I've got you John, I wrongly assumed that the apps would allow for BC changes as the velocity reduces.
I've got an opinion to enter 5 different bc values at various speeds throughout the flight path all be it not a true sliding scale

That's what I am talking about . Those 5 BC entries and the velocities would give better trajectory prediction . If it only takes a single velocity entry and a high and low velocity is quoted just go in the middle of the velocity boundary . That is still more accurate than one BC entry .
The drag function predicts the trajectory based on the stated BC which relates the actual bullet you have with a whole lot of math I don't even begin to understand . I'm a grunt not a scientist .
A G1 drag function is how a standard G1 type projectile looses velocity as it travels through the air in a standard atmosphere .
Then somehow the math relates your actual bullet to adjust that standard drag to be more like your bullet plus adjustments for atmosphere etc . In a way it is allowing for how the BC changes in the drag function but I don't think it actually calculates those BC numbers in the math . I am right at the limit of my knowledge at this point .

[Wyliecoyote]

I have muddled with this stuff for years and for me the only sure way is real empirical data. Even though I use Srelok I still test in the real world and adjust the data. As John said the BC of bullets varies with speed over their flight but it also varies with barrel twist rate when using VLD bullets. So it is very important to match bullets to your particular barrel. Brian Litz has done detailed work in this area where he started off with theoretical calculations then moved to firing thousands of rounds downrange to test his theory. Some bullet manufacturers are now giving out BCs of bullets from differing barrel twist rates where the difference between those spin rates is considerable and often well off the marketing numbers John mentioned.

You can do something yourself that has been done for years by long range shooters where by examining pin holes through targets at long range at say a 1000 yards can give you feedback on whether the bullet and twist are working as they should. By shooting 10 rounds through the target at that range you can flatten out the bullet holes and examine the pin holes, the point where there is first contact of the bullet meplat hitting the paper. If all 10 of the pin holes are high of center the bullet is completely stable and spinning about its centre of axis and you are getting maximum BC value from that bullet. If the pin holes are in any other orientation than center high, and some by pure chance can be center high, the bullet is not at optimum spin rate. It has a wobble or off axis spin where your BC input won't be correct at any range using any app. This is why it is imperative to use real world feedback and not blindly trust what you are being fed.

Three side notes. If you have Strelok on a phone right now, it will not transfer to a new phone. How they are doing that is a mystery but I know two people that could not transfer it and use their old phones purely as ballistic calculators.
That range of a 1000 yards is used because it shows up the flight error very clearly and better than say 500 yards might.
The last note is that no matter what you say, until the bullet is spinning about its axis of symmetry, and hopefully its center of gravity, you will never achieve the best possible accuracy with that bullet and barrel twist rate combination. The BC variation of random frontal area the bullet presents in flight cannot lead to consistent trajectory bullet to bullet. It results in vertical dispersion at all ranges and erratic windage at longer range were a bullets random BC drifts accordingly. So it is possible to see a sub half inch vertical slot at a 100 yards, that may impress some, become an open 20 inch group at a 1000 yards. A simple examination of the plain old little pin hole can tell you a lot whether you shoot short range benchrest or long range Fclass.

[JohnV]

That pin hole test is ok but at close to mid range some bullets fly nose up to the axis of trajectory so on the target they can appear to be going a bit side ways and their not . This is a dopler radar image of a military FMJ flying nose up . Now for those that can't see that , Check out the angles of the shock wave on each side coming off the meplat , they are not the same angle so that proves it's flying nose up . Spin drift is the bigger problem for barrel twists and too much spin can also spread the group . Barrel twist calculators are much more advanced now than the old Greehill formula and do a pretty good job . For the short and long ranges using the one rifle twist rate will always be a compromise . We should also not that the cannelure is causing nearly as much turbulence at the boat tail as you would see at a flat base . So how much good is the boa tail really doing ?
At supersonic velocities and with the cannelure nearly nothing .

[Bazz]

Not sure what sort of phone you have peterozrover when you mention android but Strelok Pro is still available on the Galaxy app store. I just installed it on another phone only a few weeks ago. Highly recommend.