9 o'clock vs. 3 o'clock wind drifts different with same wind velocity???

[Broz]

OK I'm convinced enough to start playing with and learning CE. However my cell phone wont make me happy for now ( I find them clunky to use ) I would like to know if there is an affordable program for my lap top or is the cost why so many are going cell phone.

I would like a good bullet library that is tweekable for B.C. that the program will correct for all the normal stuff with the addition of SD and CE without having to add in speculation or another set of numbers and latitude correcting for CE as well

Basically just enter the facts and push the button (lap top, because I use the armor plated phones that are just a phone, heck I even manage to destroy them once in a while

Which program do I want and who do I get it from!

You are describing Shooter. It also will give you shoot angle by pointing the phone as well as azmuth.

You could look for a used droid X on e-bay , then once you get shooter on it switch the service back to your other phone. Then you could carry it with you hunting or the range.

Jeff

 

[Broz]

Load Base 3.0 will do it too but I am so computer challenged I could never get it to work. Worst shooting I have done in years. I paid big bucks for it and if I could give it to you I would. It is still on my desk top. I think you would like the Droid and shoote route. Plus it has a big screen and I can see it with out readin specs.

Jeff

 

[shortpants]

Jeff, great shooting as always! I'd love to attend a shooting siminar of yours. Do you have this years dates worked out? Also it sounds like the Shooter program is very similar to my Bullet Flight program except my app was $30. Oh well it seems to be an amazing tool. It's got some features that I don't even know what they do. For years I have tried using ballistic programs and have had great success with getting my elevation drops to match up pretty close but my windage corrections have always been off. I have always just measured wind with a wind meter and then shot and wrote down the moa correction for that reading on my drop chart. I always have needed around 1.5moa more correction than any program would tell me I needed at 500 yds. That is the range I typically test wind at. In the past my shooting skills and equipment have limited me to this range ( factory gun/factory ammo ). I'm working on the equipment part right now so the sky is the limit in the near future. What I have finally realized is these ballistic programs are not the problem but instead it's my lack of ability to properly dope the wind. A 3mph wind meter reading while laying prone does not mean I should hold for 3mph. As soon as the bullet leaves the bore it climbs high above my position. The wind speeds up there are obviously faster than what is felt at ground level.
Example 1: Shooting in WY earlier this year at 530 yds. I shot 3 times at a 12" steel plate missing all 3 shots. I held no wind because I felt no wind and did not give SD or CE any thought at all as most probably wouldn't. I drove up to check the target to find 2 of the shots had gone through the leg of the target about 1 1/2" apart which puts it @12" from the center of the steel plate. After adjusting I shot a 2 1/2" group into the center of the plate. Now going back through this using Bullet Flight I find that nearly 2" of that miss was the effects of SD and CE and the other 10" was a wind up in the bullets flight path of @ 5mph.

Example 2: Shooting 500yds here in AZ with a wind reading of 3-5mph from 8 o'clock I dialed for a 4mph wind and fired a few shots very constantly hitting right of the 12" steel plate between the plate and leg of the target. Just the factor of SD and CE alone might have been enough to get me kissing the edge of the steel plate and by changing that 4mph to 6mph I'm right in the middle. After correcting for my mistakes I shot a 3" group into the middle.

I realize these 2 examples are quite elementary for a lot of you on this site but they have proven to me the importance of learning to read the wind properly and not doing what you see on tv and also not ignoring the effects of SD and CE. They are real and they are constant which makes them simple to factor in especially if your using a program that does it for you. A high B.C. bullet sure helps as well. I hope this thread others as much as it has helped me!!!

 

[Broz]

Shortpants, my shoots are just for fun at no charge and are held the second Sat of each month Apr through Aug. It would be great to meet you and do some shooting at one. You would really like the winds there. They come from many angles and across 3 or 4 ravines, so they will mess with ya pretty good. Your experience is same as mine. It is vey easy to under estimate wind for a few reasons. I find it a good practice to estimate to the high side too.

Jeff

 

[SBruce]

Broz It sounds like you did very well for our sport. I don't actually know if CE would have made a difference. Here is my counter point (just in general): It is our Scope adjustment ratio.

Example: If a person uses a scope with 1/4 moa adjustment there is only a certainty of a little under 2 inches of accuracy from the scope adjustment at a little over 1500 yds. and that is up, down and left right. that in itself is 1/2 moa in total or about an 8 inch circle.

If you click stop on your scope had settled to the other side of true zero how much would that be off if it were in the correct direction. How much is a click on your scope ( I don't have one of the same brand) It is an interesting counterpoint and yes I am still confused by CE

Ken, can you clarify this some? It went right over my head. I am failing to understand how one click of 1/4 moa translates into a possible 8" circle or is only 2" accurate? Seems one click would move the bullet 4" (in a perfect world).

 

[ken snyder]

SBruce I will give it a whir. If a scope has 1/4 moa adjustment clicks there is no guarantee that one will be at the scopes true zero poi ( no wind or anything just angles) the most a 1/4 moa click can be off is 1/2 the value or with a 1/4 moa scope it would be 1/8 moa a 1/8 moa scope would be 1/16th of a moa and so forth the reason it wont get any bigger than that adjustment wise is that if it is more than half its adjustment then flipping either one way or the other depending which way it needs to go will reduce the aim point error. If we take take a 3/16 moa that is too much to the right and click it back to the left it becomes 1/16th not enough to the left which is closer to true zero than than the origional 3/16 ths off. without having a precise favor and knowing what it looks like at long range the guaranteed aim point can be no better than the the origional 1/4 moa. But it gets better even yet.

moa is an angle not a distance like miliradians, If you put a book up against a wall laying down and start raising the end closest to the wall it gets further away from the wall with every degree that end is picked up and the trajectory starts making a large oval taller than it is wide because it is not known whether the verticle is too high or two low, so here we have about an 8 inch circle for certainty and as the yardages increase it starts to get bigger even faster because now we are playing yard darts too and the less of a vertical target the bullet will see kind of like leaning back a flat target at a 45 degree angle( an eccentric radius for lack of better words) The combination works about to 8 inches with a 1/4 moa scope at about 1550 yards. This is from practical shooting experience from making bases and rings that have been adjusted to optical center and impact coinciding. (from your scopes point of opinion)

 

[SBruce]

Ok, I can see how 1 click could maybe only move the poi 2" now. Likewise, it makes sense that the movement of 1 click may be 6"(@ 1550 yds). Resulting in the possibility of a 2" error from what we're expecting.

I can visualize the analagy of leaning the target back at a 45 angle and it appearing smaller also, in fact that is why I used to range game animals (via a reticle) with the vertical portion of their anatomy rather than the horizontal (or what "appeared" horizontal). When they were standing up, their anatomy was surely vertical, but we don't know if they are perfectly broadside or not.

I guess I'm still not seeing the 8" circle theory but that's ok, it's probably my density. Been a long long time since Geometry or Trig and I've forgotten what I once understood about chords, arcs and radiuses, and I don't even remeber alot of the other terms we used to discuss.

 

[ken snyder]

Thats ok I'll give an example that hopefully will not cloud things up for you. this example is only trajectory angle. I'm pretty sure most of us has shot at a rock on the ground. that rock is on a road with a steep slope going down hill and it is only about 300 yds. away and it is shot at a few times. We then go and look at the impact marks in the gravel and to our horror we see that they are really far apart and we haven't missed a target that far since we were 5 years old. same thing occurs with a target at long range but this time it isn't the angle of the road it is the plunging angle of the bullet on a vertical target. Plus you forgot to double the moa because we don't know which side to favor for left and right as well as up and down and this is a worst case scenario provided that the scope is actually following its own rules ( those that can do a good job favoring exempt). My example a worst case scenario regarding the scope. Another good example is having to tweek the scope numbers with the question am I correcting for the bullet or the scope when everything is going very well - could be dead on or an 8 inch oval that is entirely click oriented, so I head for the worst case scenario because None of us has ever missed a target when every thing adds up to the best case scenario. actual scope value no favoring

 

[Topshot]

Hey just for fun guys, I have a trick question for you.

When would a bullet fired from a right hand twist barrel not drift to the Right?

When the rifle is fired straight up.

 

[Jumpalot]

How about south of the equator?? Which has a greater effect, coriolis or spin drift??

 

[Bart B]

moa is an angle not a distance like miliradians

Ken, there's no mention of distance in any one of the four world-wide definitions of a milliradian. They're all fractions of a circle; 1/6000th, 1/6283rd, 1/6300th and 1/6400th. Therefore, by definition, a milliradian is an angle.

If a scope has 1/4 moa adjustment clicks there is no guarantee that one will be at the scopes true zero poi...

What's a "true zero poi?" Never heard of that.

the most a 1/4 moa click can be off is 1/2 the value

I've measured errors as much as 80 to 90 percent of a click's value for the first one. But subsequent clicks in the same direction are typically pretty close to value.

If you want to really see some interesting stuff, measure how much the reticule figure-eights around the target as the power's changed from limit to limit on variables. This makes visible the reason why benchresters use fixed power scopes.

....We then go and look at the impact marks in the gravel and to our horror we see that they are really far apart and we haven't missed a target that far since we were 5 years old. same thing occurs with a target at long range but this time it isn't the angle of the road it is the plunging angle of the bullet on a vertical target.

If you calculate the bullet's angle of fall then compare it to that road with a steep slope, you'll learn the road had a greater angle to the horizontal than the bullet's trajectory does. And I think you meant to say "it is the plunging angle of the bullet on a horizontal target." as that's what causes large horizontal errors in range for bullet impact relative to the target.

 

[Bart B]

When would a bullet fired from a right hand twist barrel not drift to the Right?

When it started into the target 1/1000th of an inch in front of the muzzle.

 

[Michael Eichele]

How about south of the equator?? Which has a greater effect, coriolis or spin drift??

Spin Drift.

 

[Michael Eichele]

Hey just for fun guys, I have a trick question for you.

When would a bullet fired from a right hand twist barrel not drift to the Right?

When it is fired in a vacume.