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

[ken snyder]

A Miliradian Is always 1000th the distance to the Target no matter how far or close we are away to the Target and independent of angle its mesaurement is expressed by the distance. mili 1000 raudus is length from the center to the edge. moa is an arc angle so its distance to a horizontal surface is only correct at 90 degrees because the length increases the further we get away from from 90 degrees kind of like pushing a basketball up against a wall and then measuring how far it is to the wall at different angles from the balls center.

When we tweek our scope numbers to make our charts. you will notice that our yardage corrections do not match the mathematical trajectory it has bellys and swamps in it (High low low High right left right left etc) things that a bullet in flight can not do consistently and repeatedly but are ever present and accounted for by tweeking the numbers and favor. So 1/8 th is really close to two inches at 1,550 we do not know which direction because it could be both vertical and Horizontal which gives us a 4 inch oval. the difference between a 4 inch circle and an 8 inch is only 2 inches of radius. 2 inches at 1550 yds is a measurement of angle of about .000035 per inch, scopes are not that accurate we correct them at different yardages

 

[shortpants]

When the rifle is fired straight up.

I can see why CE would not exist in this scenario but am failing to understand why spin drift would have zero effect on POI?

 

[ken snyder]

I could not figure out why we were having a difference of opinion on what a Milliradian was so I did some research. There are differences The milliradians I am speaking of were developed specifically for artillery firing solutions. it is always 1,000th the distance to the target. it reduces the complication and error of plotting trajectories and distances. There are numerous Milliradians and definitions, Even the country where they are used changes them. Which leads me to ask which kind of Milliradians are on our scopes. Where were they made is there a unified definition. I'm thinking that could be quite a few inches just by manufacturers location and interpretation

Not to jump up and down with joy but yes actually I am. one more misunderstanding shot full of holes. I'm thinking that my controversial 8 inch circle with a 1/4 inch moa scope might not be the worst you can expect it looks like it could actually be the best to expect

 

[ken snyder]

I Googled"Ballistic true Zero"and the very first article described true zero and is by Randy Wakeman. I don't know how commonly it is used as a term but I have been using it for quite a while and actually found his writings to be somewhat contradictory to other writers reguarding a scopes measurement system in terms of accuracy as well as mine. I think a good article is "mil versus mil versus mil" - and then quite a few scattered articles on other difficulties from our scopes

I was a Hard sell for CE. one of the articles uses Leo products as an example and it looks pretty bad but I find it true with all of the scopes.

 

[Bart B]

I could not figure out why we were having a difference of opinion on what a Milliradian was so I did some research. There are differences The milliradians I am speaking of were developed specifically for artillery firing solutions. it is always 1,000th the distance to the target

Check out:

Angular mil - Wikipedia, the free encyclopedia

'Twasn't always 1/1000th the distance to the target.

If you do the math using the USA adopted version in the early 1900's of 1/6400th of a circle then do the math, at 1000 yards a milliradian is 35.3429 inches. It wasn't until the 1950's that the metric version was adopted by NATO.

 

[sp6x6]

Ken, Are you shooting a 1/4 moa scope? And looking for finer adjustment? Two friends of mine both shoot .125 NF 12-42. They are both W record shooters, the one just bested some of his own and set 2 new @ 1000 this previous summer.

 

[ken snyder]

I did some more checking around and there are at least 5 different Mills all of them measure different and depending on what the scope was based off of changes the size of a moa, true mil, us military mill, Russian mill, European mill and sweedish mill. Havent read yet if there is also a Japanese or a German mill. the swiss either have gone to the NATO will or soon will. I'm still looking at correcting for CE and it is once again starting to look like it isn't going to do much except give a guy something to play with without the use of a dedicated military type long range shooting system with its own PDA and programming for the system. I'm still looking but it looks like for me the best is still sighting in at range twisting the scope and using the dots and there probably never will be anything that even comes close to the accuracy of being dialed in because it is already there.

 

[paphil]

Then there is the feed mill, the cotton mill and here in Pa we even have some steel mills.....

 

[ken snyder]

SP6x6 I use 1/8 moa scopes and build my own rings and bases and correct them so that true zero is optically centered at the expected yardages, this gives me very very little scope error and then on my 1/4 moa scopes I do do the same thing and use the dots (Long range hunting) there is probably less than 1/4 the scope induced error to non existent in doing it this way. I am 100% dedicated in rifle purpose and break them down into 500 yd increments. I always have my wife as a hunting partner. we never double up on rifle designs. we always have the extreme accuracy capability of two sets between the two of us which is 0 -1000 or 500 - 1500. I do have general all purpose hunting rifles for 300 - 1000 but never find the need.

 

[Bart B]

SP6x6 I use 1/8 moa scopes and build my own rings and bases and correct them so that true zero is optically centered at the expected yardages, this gives me very very little scope error and then on my 1/4 moa scopes

How do you determine your scope's optical center?

Does it align perfectly with the scope's mechanical center?

I ask because I built my scope collimator such that the collimator's optical center is aligned with the mechanical center of the scope rings that hold the scope under test. This puts the scope to be tested in with its tube axis aligned with the collimator's optical axis. Then its easy for me to put the scope's adjustments (optical axis relative to the erector tube) on the scope's front and rear lens' optical axes.

 

[ken snyder]

BartB the way you are doing it is a very good way of doing it and far exceeds the majority of mounts I see. I don't use that method on my trued mounts and rings but use it on general mounts that a person wants a good trouble free mount. I make the rings and mounts correct them as a unit and then intall them on the rifle and finish them on the rifle. ( essentially built on the rifle) I have standard known bases to work from after shooting the rifle the and they are corrected from that point. MY bases are from 12 - 16 inches long for the machining process and then cut down to an approriate length which also includes a length that is appropriate for the scopes eye relief and intended shooting position. (recoil included). The main reason for making the Blank so long is to get a good taper reading if they are made to the correct length then the length simply is not long enough to get an accurate reading as a product of taper per inch.

Part of the problem is that rifles do not cast out the bullet at the same angle as others whether its hook or a slight barrel to action alignment problem.

Due to things like face placement and cheek welds the only determining factor if it is dead on a click is the opinion of the shooter ( still looking for a one hole 1000 yarder) but happy to tweek to satisfaction. I'm currently have 3 of my better shooting rifles equipped with a ship it to you Base or B and ring set up but so far the only benefit I see to them is that I get twice the price for the same thing any one else makes and sells ( failure). I have 2 scope set ups on television, sort of the first one is hanging around in the back of an archive waiting to be aired and the second one is supposed to come out this summer but still have no idea which network or cable company it will be on. - so much for men and mice - If I was rich I would have my sons of Guns TV show and we could all be filmed drinking coffee and acting normal a show for bed time guaranteed to put people to sleep

 

[Bart B]

Part of the problem is that rifles do not cast out the bullet at the same angle as others whether its hook or a slight barrel to action alignment problem.

Ruger 77's used to be notorious for horribly misalignment between bore and receiver axis. As long as they're no more than 10 MOA out of alignment, it's usually not a problem.

 

[ken snyder]

The last part of my last post does not read correctly. Suns of guns is not my show.

( if I had my own Suns of guns show )

But you all knew that anyhow ? - sorry

 

[Topshot]

I can see why CE would not exist in this scenario but am failing to understand why spin drift would have zero effect on POI?

Actually Ce does exist in this scenario, the bullet would drift North-West in the Northern Hemisphere and South-West in the Southern Hemisphere.
It would not drift "Right" as gravity will be acting on the base of the bullet and it does not roll over and yaw in a normal type trajectory. Also, which way is right anyway to a barrel that is pointed straight up? LoL


Maybe someone might like to chip in and explain why a bullet drifts right with a right twist barrel?