peterozrover wrote: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
on_one_wheel wrote:Strelok Pro works extremely well.
It will do what your looking for plus much much more provided the data you enter is accurate.
Wyliecoyote wrote:on_one_wheel wrote: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 wrote: . 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 .
Wyliecoyote wrote: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.
JohnV wrote:on_one_wheel wrote:JohnV wrote: . 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 ?
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
peterozrover wrote: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
on_one_wheel wrote: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