Long Range 101 Part 73 - Coriolis Effects on Rifle Bullets

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Күн бұрын

Coriolis effects on rifle bullets explained in detail. Yes, the Earth's spin affects the apparent flight path of a rifle bullet when fired at extreme long ranges. How much do you adjust for coriolis? Watch this!
NOTES (to burn into your brain):
1. Horizontal Coriolis Correction
- Deflection is the Same Irrespective of Direction of Fire
- Northern Hemisphere: Always Deflects POI to RIGHT (adjust fire Left)
- Southern Hemisphere: Always Deflects POI to LEFT (adjust fire Right)
- Magnitude Depends on Latitude
- Poles: Maximum Deflection
- Equator: Zero Deflection
2. Vertical Coriolis Correction
- Deflection Changes Respective to Direction of Fire
- Shooting Due North - Deflection is ZERO
- Shooting Due South - Deflection is ZERO
- Shooting East -- Deflects POI HIGH (adjust fire Down)
- Shooting West -- Deflects POI LOW (adjust fire Up)
- Magnitude Depends on Latitude
- Poles: Zero Deflection
- Equator: Maximum Deflection
All the music in this video was created by TiborasaurusRex, an unsigned artist.
Song Titles: Wadi Watir, Particle Jam, Magnetic Night
Music and Lyrics by: TiborasaurusRex
Instrumentation and Vocals by: TiborasaurusRex
Recorded by: TiborasaurusRex

Пікірлер: 567

@TiborasaurusRex 5 жыл бұрын

Come train with Rex!!! It would be an honor to meet you in person! rexdefense.com/

@rustynails5797 5 жыл бұрын

Trex The earth isn't spinning and no adjustment is used for the rotation of the earth . I defy you to make an actual video and show the results of shooting in various directions and how you calculate the spin and various directions on the fly . Coriolis stupidity A hunter sees a deer off 600 yards away . The hunter now has to figure out which direction he is shooting and calculate the 300 to 400 yards per second the earth is spinning . When it would be hard to calculate the lead you'd need to hit the target walking then add the speed of the rotating earth . The shot would be impossible . Yet you know you hit a target of same distance pointed in any direction all things else being equal , like no wind . You need to rethink your position rather than regurgitate the indoctrination you've learned . To summarize, long range shooting would be impossible with a target moving multiple hundreds of yards per second . There is no way you could hit a target moving 600 -700 miles per hour ..

@ImAManMann 5 жыл бұрын

@@rustynails5797 Says the person who has never done any long range shooting. lol There are plenty of documented examples of shooters showing the effect in action. You even obviously ignore the point of the video where he states that it is @ 1000 yards where you really start to see the effect on your shots. I challenge you to make a video disproving it, 1000 yards in all 4 cardinal directions.... oh... you won't do it because you are full of shit... got it... just like all the FEs.

@rustynails5797 5 жыл бұрын

@@ImAManMann my first reply didn't post You're as clueless as T-Bone Rex. Name a long distance shot you've made and the amount of Coriolis adjustment you used . I'd bet you can't even tell me how fast the earth is spinning where you are right now , Well dud ? You appear clueless with your lack of comprehension of my first post in this thread I'll make you a $10,000 bet you can't list a shot you've made using the speed of the spinning earth and duplicate it in a live test . . The same goes for T bone Rex I'll bet neither of you understand what you are saying . It should be an easy 10K for you guys of such knowledge You obviously don't get the problem Of how shooting less than a 1000 yards wouldn't be a problem if the earth is actually spinning between 300 and 388 yards per second in the US as does the maker of this video show his ignorance . This goes for any stud out there . Name the shots using the speed of the spinning ball and your adjustments, then perform the shots . I'd bet most of you Coriolis spinning ballers don't even know the supposed spinning speed of of the earth where you are now let alone going to a more northern or southern region and have never used a Coriolis adjustment Put your money where your mouth is .

@ImAManMann 5 жыл бұрын

@@rustynails5797 So typical, trying to change the subject. Go out and do what I said... oh you won't do it? Of course not. If you will do it and film it I will complete your challenge. You will be required to place the 10k into escrow and sign a contract detailing the stipulations which we both agree to and I will be happy to complete the shots. A lawyer will need to be retained to deliver me the payment upon completion. I will also require you to fly to the location on the day I make the shots and you must say on camera when I prove you wrong that you were wrong, I was right and that flat earth belief is stupid. You up son, because I am.

@rustynails5797 5 жыл бұрын

@@ImAManMann No subject changed except by you . Do you not understand what I wrote in my challenge ? I'll go anywhere in the continental United states . If you lose you also pay my plane fare and I'll walk away with your 10K and the plane fare . Let's check your confidence level . Turnabout is fair play . I'm good with that the money being held by a 3rd party I'll also rent a donkey and when you lose you can kiss my ass on camera . I'm not afraid of your arrogant ignorance . but I'll bet you won't have the guts to go through with it . 10K is quite a bit of money for someone to put up that doesn't have a clue what they're talking about . If you fail to use the calculated spinning speed of the earth in your calculation for your area you forfeit the bet and airfare Now tell me how much adjustment for each direction and what is the area you'll be performing these shots you'll use in each of the directions ? I'll assume it'll ' be none to a 10th of an inch not taking into account the 700 plus miles per hour of the spin . This will invalidate the bet and you forfeit the bet and air fare . I don't think you have a clue on how much adjustment would be needed . If you don't use the speed of the spinning ball , it invalidates your argument and the bet and you forfeit the bet and airfare . Of course if you let me know now , You don't plan on using the spinning speed of the earth, it invalidates your argument and I won't waste my time any further on your cluelessness . I've been shooting for over 50 years and have never used any Coriolis adjustment . What is your location area ? So I can do calculations to make sure you are factoring in the speed of the earth .? Let's come to terms bud I'm ready to take your money . I'm guessing you're a don't know what you're talking about chicken and this will never happen . You aren't the old man in this conversation unless you're over 61 years old , well son ? You're also not the smart man in this conversation . Lets rock

@tightspotpro6755 9 жыл бұрын

This is a general statement not about this video exactly but the comments in this section have drawn it out of me. Rex has done a fantastic job and put an extreme amount of work in this video series. I really hate the haters. Sometimes people just try and look for an error or what they think is an error and jump at pointing it out. Hey put out your own video. I am betting you don't have .5% of the over all knowledge Rex has put together for educational purposes on this subject.

@fortbuilder100 10 жыл бұрын

Rex, I agree with redmanrubber here. Your one comment "your target won't get there in time" explains it most clearly. Most often Coriolis "Effect" is construed as a hypothetical force. However, it is not a force, rather it's an "effect" as a function of time. Distinguishing between "force" and "effect" should or at least might clarify this for those still in question.

@puncall751 7 жыл бұрын

I have watched a lot of other videos here, and most are pretty good. Rex has done an excellent job of presenting the information, and his knowledge is vast and complete. I have been shooting handguns, rifles and shotguns for more than 60 years, and have probably learned more about the technical and scientific areas of the sport from these videos. I want to thank Rex for the vast amount of time he has spent preparing this series, and for sharing his knowledge. This is an excellent series and I would recommend it to any shooter, new or old.

@TiborasaurusRex 10 жыл бұрын

Great question - perhaps I should have elaborated on this point in more detail. At the distances we are shooting, horizontal Coriolis effect is a function of latitude. Out to 2000m, azimuth differences will have no effect on our horizontal correction. Beyond 2000m, you will start to see a small effect due to azimuth. If you look at a TFT for a 105mm gun, the horizontal correction @ 5000m for due North is 0.4 mils L while shooting due East it is still only 0.5 mils L (a very small difference).

@aznmutt15 3 жыл бұрын

The vertical drop/rise seem like it was explained wrong. Though it does come into some effect because of drag, but it seems like the eotvos effect is coming into affect. Firing east means that the bullet has a faster velocity in the fixed frame of reference outside of the earth. In other words it is going faster than the spin of the earth. While firing west, the bullet is moving slower than the spin of the earth. This affects the centrifugal acceleration acting on the bullet. Higher the v, more acceleration acting opposite to gravity. This will raise or drop the net acceleration acting upon the bullet.

@ashy1423 5 жыл бұрын

A really great explanatory video. Thanks for sharing. Ash🏴󠁧󠁢󠁳󠁣󠁴󠁿

@Oro4MadNess 10 жыл бұрын

Wonderful job Rex. Tough concept-excellent knowledge. Great mentoring style.

@Mrichard1991 10 жыл бұрын

I've been watching these from the beginning and these videos have been just great! Keep up the videos.

@Captaindan7141 9 жыл бұрын

It took a while, but this makes PERFECT SENSE now. Thank you so much.

@dukes5f5 6 жыл бұрын

I've been working through the videos as time allows. Robert McCoy's "Modern Exterior Ballistics" that i have through an Inter Library Loan at the moment, does a great job on the mathematical side of Coriolis from Flat-Fire Vacuum to Point-Mass Trajectory applications. The book really helped answer some of the questions from this video. Rex Sir, you are the man. Thank you so much for offering these videos to us noobs. My level of learning over the past few months has gone up exponentially thanks to your expertise!

@redmanrubber 10 жыл бұрын

About the only info I've seen so far that's made sense in my head to explain Coriolis. So thank you Rex!

@TiborasaurusRex 10 жыл бұрын

Thanks for watching, sir.

@TiborasaurusRex 10 жыл бұрын

Think of the rotation of the earth as a merry-go-round, if you are looking down on the north pole as the merry-go-round is spinning CCW. If you are throw a ball straight into your momentary velocity vector (ie straight into the spin or straight away from it) at any given position from the spinning merry go round, the constant rotation in a circle will still cause a horizontal deflection to the right. Perhaps I will add a new illustration to explain this aspect in more detail.

@storkyring 10 жыл бұрын

super explanation m8 well done very informative

@Battleaxegunner 10 жыл бұрын

Thank you so much for your grand knowledge.

@jsnyper4357 7 жыл бұрын

Nice video and the music rocks!

@joneifer8070 3 жыл бұрын

That is complicated. Thanks for the amazing explanation.

@ExON00 10 жыл бұрын

I'm wondering the same. I thought it was max horizontal deflection, zero vertical when shooting N-S. And zero horizontal, max vertical when shooting E-W. I think horizontal correction should be multiplied with the cosine of your heading in relation to a N-S line. If anyone knows better, Please explain

@hbarwickjr 6 жыл бұрын

Is there a part 72? Can't seem to find it. So far haven't found it through KZfaq search. Thank you so much for the wealth of time you have given in providing such a wealth of information! Recently purchased a sa m1a and gleaming thru your vids to get the most edge out of it possible.

@spicychich1718 5 жыл бұрын

archive.org/details/youtube-v-LB6qwuDYs

@ByBelgian 10 жыл бұрын

Great video! It makes my head spin... literally :D

@milamcshanks8192 10 жыл бұрын

Does this ballistic table (v1.45.25) render the ones from the previous videos obsolete?

@TiborasaurusRex 10 жыл бұрын

Excellent commentary! Thanks guys, you are all a great help :-)

@grantpeens9605 6 жыл бұрын

Hi Rex, awesome series. I've noticed that Part 72 no longer exists. Where can I see the Spin drift video and obtain the spin drift table? Thanks again sir.

@KORMMM 4 жыл бұрын

Grant Peens found it, enjoy! archive.org/details/youtube-v-LB6qwuDYs

@CriticalInception 4 жыл бұрын

Math does not create reality. I'd love to see an actual experiment that isolates the variables and proves that there's any deflection of the projectile. Flights from Charlotte, NC to LAX should only take 1.5 hrs if earth is spinning underneath. The actual time is about 4 hrs. Each way.

@benjaminbelcher2739 2 жыл бұрын

My thoughts exactly. I am a pilot and this is bogus. There is no correction for the spin of the earth when planning trips

@awatt Жыл бұрын

kzfaq.info/get/bejne/sMuhgNaXm5yRnY0.html Your answer

@jodo1971 6 жыл бұрын

How come airplanes or long range artillery does NOT adjust for Coriolis ? ? ?

@ryandewitt5704 6 жыл бұрын

jodo1971 because any artillery that we use is only good for x amount of distance the Coriolis effect only accounts for a few inches to maybe a couple feet at those distances if you can play some mortar or artillery within a few feet of your target your target is going to take damage! And if you were in a airplane or helicopter you're constantly adjusting to stay on the correct line

@max5250 6 жыл бұрын

Actually, long range artillery do account for Coriolis (consult any Howitzer manual), airplanes constantly adjust speed, direction, altitude etc, and do not have to do correction for Coriolis (if they were 'shoot' from airport to airport, without actively changing direction of flight, they surely should account for Coriolis or they would miss destination airport badly.

@rustynails5797 5 жыл бұрын

ryan dewitt The earth is supposed to be spinning at 300 to 400 yards per second in the united states . It appears you don't know what you're talking about but don't let a little thing like that keep you from making clueless comments. Now you should be able to see the error in comment . Please explain to yourself how you'd only need a couple feet of correction when the earth is spinning hundreds of yards per second.

@hopmajibhohepeajibho7595 Жыл бұрын

@@rustynails5797 the plane is spinning with earth

@owenwatts8642 3 жыл бұрын

Do we not need to account for coriolis in our super elevation standard? Just like the atmospheric variables? If we dont are we not adding more corriolis corrections onto already embedded corriolis corrections? Eg if I set my super elevation happening to fire eastwards, and then knowingly fired eastwards at the same lat and added vertical coriolis correction, wouldnt I be doubling up?

@jameswalker5813 6 жыл бұрын

Hey Rex, Great series!!! Can't wait to go to one of your classes. I have a question about Spin drift and since that video went away, can you point me towards a place to figure my spin drift? Thanks and God Bless.

@zandyllatos7473 5 жыл бұрын

Thank you for this video. While I was well aware of how to compensate, and had a general grasp of why this is needed, I was always a bit confused how this apparent force worked in detail. Since in general physics we negate this effect, as well as in the military. Your explanation cleared up that question. The only thing that eludes me is why the vertical correction does not change depending on your direction of fire. Common sense would dictate that if you fire Due E or W, it would be 0, since your target is at exactly the same axis as you are in the direction of the Earth's spin. Which means there would be no difference in velocity. Obviously I am missing something here, but I can't figure that out.

@kfm908 4 жыл бұрын

they don't allow for any rotation .It's all lies!

@marioprzepiora 5 жыл бұрын

Great video and correct explanation of Horizontal Coriolis effect. However, what you call Vertical Coriolis Effect (and therefore correction) is actually an Eötvös Effect.

@Physics072 3 жыл бұрын

I think the Eotvos effect is the change in perceived gravitational force caused by the change in centrifugal acceleration resulting from eastbound or westbound velocity of a a object that is following the curvature of the earth. (not true with a projectile) It is a add on to the Coriolis effect, The first term is the vertical Coriolis effect, the second term reflects the upward centrifugal effect of moving over any spherical surface, also non-rotating ones. Bullets are not attached to the earth like ships at sea. I think the Eotvos was used to explain why objects had different weights on ships moving West vs East. For objects not following this curved path the centrifuge component (Z) of the equation can be omitted leaving just the first part which is related to the coriolis effect. Bottom line: I think Trex is correct on sayings its Coriolis.

@guns4funcajanajustin 10 жыл бұрын

Good info. brother!

@kjelladrian3205 2 жыл бұрын

Could anyone please explain how to do the calculation for vertical deflection manually?! Please give me an example where you're standing on the equator, 0 ° lat. shooting straight eastward 90 ° bearing (max deflection). Maybe this will get me on the right track. I've tried transforming degrees to radians and then using the 'rad' function on my computer's calculator, but it seems I'm doing something wrong ...

@UTurnCub 8 жыл бұрын

Hi Rex, nice explanation. I think it is worth pointing out a couple things regarding the Vertical Deflection equation (at 20:10). First, this doesn't actually a calculate vertical deflection, but instead gives a correction factor for bullet drop. The result must be multiplied by the calculated bullet drop to get total bullet drop (and then you would have to subtract the total drop from the calculated drop to get vertical deflection). Second, the average velocity should be used, not muzzle velocity. With that said, in my opinion the entire equation is overly complicated, and can be written almost identically to the Horizontal Deflection equation, except with cos(Lat) instead of sin(Lat), and with the addition of sin(Azimuth). Vertical Deflection = Ώ · Range ft² · cos(Lat) · sin(Azimuth) / Vave or simpler still (in my opinion): Vertical Deflection = Ώ · Range · TimeOfFlight · cos(Lat) · sin(Azimuth) Horizontal Deflection = Ώ · Range · TimeOfFlight · sin(Lat) Hope this helps.

@RecreationalSniper Жыл бұрын

How do you convert the result from the equation to MOA or MRads?

@ExON00 10 жыл бұрын

Thank you. I couldn't find that document, but it seems to be an observable fact. My Shooter App also gives me the same horizontal correction regardless of azimuth. Still can't get my head around the physics of it. I'll have to do some more research, but its getting to a level where its hard to find reliable sources. Which reminds me, I'm going to buy Bryan Litz's book, does he touch on this subject?

@RecreationalSniper Жыл бұрын

Is the deflection in units of feet/inches/moa? For instance we were shooting 1804 yards Southeast to Northwest, Latitude was 34.756, a couple weeks ago with my 6.5 PRC so with 5412 feet being the distance in feet and the V-ave equating to 1729 fps I get a value of ~0.704 horizontal deflection. Would that be in inches, feet, MOA or mrads?

@ManzellaBob 4 жыл бұрын

Horizontal is influenced by direction. Shooting east or west near the equator would vary much less than shooting north or south.

@Job32Elihu 4 жыл бұрын

Rex, what if the rifling of your barrel was spinning the bullet opposite the normal spin. Would that change the amount or direction of the coreolis effect??? Thanks!

@buddsmith6425 8 жыл бұрын

If the horizontal Coriolis effect is direction independent, why not also show a graphic of the effect in the east/west direction? I can understand it in the north/south direction, but not the east/west.

@TiborasaurusRex 10 жыл бұрын

To get "Ave Vel" in units of fps, take your distance to target (ft) and divide it by the time of flight (sec). Plug that into the equation and you should be good.

@rafaelpossobon 3 жыл бұрын

Hey!!! Learning a lot here! Thanks Rhesus awesome lessons! Video 72 ia missing 😫

@johnlee4249 7 жыл бұрын

Thank you Rex for all you did & do, the time & effort you put into this shows, these are fantastic instructional videos. Hope all is well with you and your family.

@eladnonnac7529 4 жыл бұрын

What you call vertical coriolis is really Eotvos Effect. Gravity is lower heading east because of centrifugal acceleration. When moving eastbound, the object's angular velocity is increased (in addition to Earth's rotation), and thus the centrifugal force away from earths center also increases, causing a reduction in gravitational force. Less gravity when a bullet travels east, more gravity when bullet travels west. I like your video series and I try to extract any info I can from it to hit first shot extreme long range. Thanks.

@natedennison1118 10 жыл бұрын

great vids but why deos the one u use have altitude but the one i have downloaded not have it

@BL-kd9lr 5 жыл бұрын

Hi Rex, thank you for your thorough work. Your explanations are the best and most consistent that I could find in the internet. Your formula for vertical drop due to inertia effects (coriolis etc) seems to calculate symmetrical values wrt easterly or westerly directions. The opposite 'orbital speed' components would result in different contributions of apparent gravitational pull (Eötvös effect) on the bullet, ie the drop component in westerly direction would be somehow larger than the rise component in easterly direction. Up to what range would this effect be negligible in extreme long range shooting?

@sooyek78 10 жыл бұрын

Hi Rex! Thank You for your work! Now: as you explained in video - shooting EW target is coming up on us or down of us (vertical component). but where is horizontal component? target and shooter are on the same plain (no difference in linear speed) ? peace!

@razormc3646 8 жыл бұрын

Hi Rex, thank you for your effort. Keep up the good work. Could you explain how the Eötvös effect is accounted for. According to my rough calulations it should become noticable above 1000 meters and reaches the same magnitude as the 'pure' vertical Coriolis effect. Is it implicitely included in your vertical Coriolis drop data?

@UTurnCub 6 жыл бұрын

Eötvös effect is just another term for the vertical component of the Coriolis effect.

@viper921ka 7 жыл бұрын

Hey Rex I have a question for your Southpaw shooters. Would a barrel with a left hand twist affect the coriolis effect of a bullet?

@skyeshore5704 4 жыл бұрын

So does elevation also magnify this coriolis effect? If you are shooting northward at a target that is also significantly lower in elevation, would that increase the amount of rightward strike on the target by any measurable amount? I assume this because the 'speed' of a point on the earth's surface is determined by its nearest distance to the earth's axis of rotation. Lower elevation = closer to the axis of earth's rotation = slower 'speed' when compared to a higher elevation? Maybe it's not enough to be measurable?

@skyeshore5704 3 жыл бұрын

@Mike Honcho I think the same principles would apply to those factors as well, they just don't have near as much effect on the bullet like the earth's spin does? Not enough relational velocity variation to measure at these small distances of about a 1000 meters of bullet travel when you start comparing earth's travel around the sun and the galaxy's rotation around it's center of mass.

@BringerOfD 4 жыл бұрын

Northern Hemi always right, South always left regardless of direction of fire. That statement broke my brain, i need a minute.

@mhe0815 7 жыл бұрын

Wouldn't it somehow make sense to have a barrel with left hand twist when shooting in the northern hemisphere in order to have the spin drift inherent in the bullet spinning leftwards and the coriolis drift act against each other, ideally cancelling each other out?

@thomaslee7810 10 жыл бұрын

Have a quick question. On the Pocket PC page, it's correct to enter just degrees in the "Heading" box, right? The pop-up box states using a different method for "field tables" I don't understand what you are referring to. Thanks

@sloairsniper 10 жыл бұрын

Hi Rex i think there is a Latitude in radians, in Horizontal deflection formula! M i right? Thanks for everything !!!!!!

@staryoke 5 жыл бұрын

Great video series! How come video 72 Spin Drift is missing or "private"? Thanks!

@jamesaldridge1459 4 жыл бұрын

Id like to know too

@KORMMM 4 жыл бұрын

archive.org/details/youtube-v-LB6qwuDYs

@bobdavidson4167 10 жыл бұрын

I apologize if my understanding is faulty here concerning your horizontal coriolis effect explanation but here it goes. Assuming the shooter is oriented North at the target, once the bullet is in flight, both the shooter and target moves East relative to the bullet. Therefore, the POI will be left not right (right?) The opposite would be true if the shooter is facing South...POI will be right, not always right for both circumstances. Really enjoying the series and your commitment in all areas of your life.

@rojoTexas 10 жыл бұрын

Outstanding as a Geology Professor; trying to push my shooting quality to 1000 yds. Thank you

@rustynails5797 5 жыл бұрын

Rojo Kelly How did it work out for you ? If you had to adjust for a Coriolis spin based on the spin speed of the earth in the US it's about 300 yards per second in the north and in the southern region about 388 yards per second . How do they justify such miniscule adjustments for such astronomical speeds of the spinning ball ? The answer for these people is you don't need to adjust for shots less than 1000 yards , Do you see how this runs amuck ? The next big problem would be, how would you adjust for the many directions and calculate a shot for each fraction of a degree off from your location . If you have the earth spinning between 300 and 400 yards per second . shooting 1000 yards with a 308 the bullet takes 1.5 seconds to hit the target . kzfaq.info/get/bejne/b8tkppSUrbfUin0.html If you aren't using the speed of the spinning earth times 1.5 seconds you aren't using a Coriolis adjustment . That's the thing nobody uses it but in order to not go against scientism and face ridicule they take their logic and put it in a box and submit to the stupidest thoughts . I'd like to hear the opinion of an educated man after weighing both sides ?

@thecheapshot1065 2 жыл бұрын

So if I chronograph my rounds shooting from east to west will I get a faster read than if I chronograph my rounds shooting west to east

@jimsmith7212 Жыл бұрын

No.

@michaelmcdonald1950 4 жыл бұрын

Hi Rex, for some reason your pt 72 Spin Drift video doesn't play. It is designated as "private video" cheers Michael Australia.

@Guide504 6 жыл бұрын

So reverse your first assertion so that you are sill in the northern hemisphere but firing in a southerly direction the differentlal in target movement and lateral bullet movement is now reversed but now the target is faster but effectivley in the opposite direction hence the bullet always moves to the right with respect to the poi in the northern hemisphere. Is this correct or am I nuts!

@max5250 6 жыл бұрын

Guide504, You are not nuts. When you are in the northern hemisphere, and fire to the North, you are moving (rotating) faster then your target, hence, your (unadjusted) shot will hit to your right of the target (you might say your bullet overtook the target due tu faster initial speed of West to East movement) When you turn around, and fire to the South, your target is now moving faster then you also in West to East direction, so your (again unadjusted) shot will git again to your right of the target (you might say your target has overtook the bullet).

@williamshao1985 4 жыл бұрын

Hey, thanks for the physics lesson :)

@fredlingenfelter7871 9 жыл бұрын

I'm very new this effect, but it didn't take much to understand it. Good explanations of it in simple terms and breaking it down well for everyone to understand. I didn't read though all the comments to see if it was caught or not, but you contradicted yourself on a couple of the concepts. You made reference to the bullet's POI being either left or right depending on shooting north or south. According to principle, the only deciding factor is north or south hemisphere and the point of lateral position. North=Right, South=Left. Poles=More deviation, Equator=No deviation. Example being flushing a toilet in the northern or southern hemisphere. In essence, north or south shots will have no effect on POI in regards to elevation or lateral deviation. East and west shots will be effected vertically as you stated, but in opposite aspects. A shot from west to east will have a POI that is high. I attribute that to decreased flight time due to the target travelling to meet the round. A shot from east to west will have the opposite effect and the POI will drop due to increased flight time with the target moving away from the round. The slides you had up stated these things, but as you talked them through you deviated from the principle. Are the slides wrong and you have experienced different results in field or did you make a mistake? I ask because you talked it through very well and it almost made sense. Please, let me know what you think. I appreciate your presentation. It was very informative.

@cloudisunset 10 жыл бұрын

Is it average muzzle velocity or average velocity of the projectile over its flight as it makes it to the target?

@jimsagubigula7337 11 ай бұрын

Although the video is pretty good, I don't think it really explains the use of the equations well and it confuses the viewers more than helping them. So, let me help clarify a few things. Another equation that can be used for the horizontal deflection, which I personally prefer, is D_h=ω*r*sin(θ)*t, where D_h is the horizontal deflection, ω is the angular rotational velocity of the Earth, which is ω=0,0000729 rad/s, r is the distance to the target, θ is the latitude of the firing position, and t is the time of flight of the bullet. The units of the range don't matter, but be warned, range and deflection will have the same units. So, if you choose meters for r, D_h will also be in meters. You can then convert that into mils using the equation mils=34,9*arctan(D_h/(2*r)). Note that D_h will be positive for 0

@mhe0815 7 жыл бұрын

Also, if the coriolis drift to the right in the northern hemisphere is a result of different linear speeds of the earth at different latitudes (which is what happens as the whole planet spins at the constant angular rate), why is there a horizontal coriolis drift as well when shooting in east/west directions where the direction, meaning shooter and target are on the same latitude (provided east/west direction is meant in reference to true north, therefore cancelling out the variable of magnetic variation). Since RH twist will always generate some spin to the right, isn't there the risk of confusing some of it for coriolis even when shooting in east/west direction? Mathematically I cannot grasp how there would be horizontal coriolis if shooting in a geographical east/west direction, the only explanation I could come up with is that the earth's orbit around the sun is also coming into play and that the earths spin axis is inclined 23.5 degrees against its plane of orbit around the sun. But that is an absolute horror to correct for in math.

@UCEBuster 7 жыл бұрын

The merry-go-round example might help. Imagine the North pole is the hub and the Northern hemisphere is flat. The outer edge would be the equator. Since we're scaling it down, we'll have you throw a ball instead of firing a rifle, to allow enough air time for the effect. Because you and whatever you are aiming at are both moving counterclockwise and the ball will be taking a straight path you can't hit the target by throwing directly at it. No matter where you or your target are on the merry-go-round your throw will appear to curve right. Only precisely at the equator (on the vertical edge of our merry go round) would you have no apparent sideways deflection (if the ride is the only source of gravity, LOL).

@rojoTexas 10 жыл бұрын

Is sin(LAT) in radians, degrees, etc? In Horizontal.

@TiborasaurusRex 10 жыл бұрын

I primarily use the US Army Research Laboratory documents and the raw peer reviewed scientific papers on these matters, they are very reliable and show all their work. I actually do not have a copy of Brian Litz's book, so I cannot offer a review or critique of the information in it. A diversity of 'opinion' sometimes exists in some of the various ballistic texts out there and so I go straight for the ARL and BRL docs whenever I can. Even the govt FMs are erroneous from time to time.

@jessicapieper8830 10 жыл бұрын

Another great video! But, I have a question about the horizontal Coriolis effect formula. How do you come up with the average velocity for the formula? The formula I've been using is a little different: 0.0000729*range(ft)*sin(lat)*t.o.f. When I do the math both ways, I get two very different answers, but I may not be correctly be using the average velocity in the formula you shared. Thanks!

@TiborasaurusRex 10 жыл бұрын

The reason for this is that a projectile will never travel in a straight line between two points on the surface of a sphere with an unchanging azimuth. If the Earth was a cylinder, this would be much more simple. If you would like to confirm this from other sources to put you mind at rest, please look at the BRL Report No. 1371 The Production of Firing Tables for Cannon Artillery (Nov 1967) page 102. The Kestrel Horus device will also confirm Hor Corr (

@jamesdaly5295 6 жыл бұрын

Why is the previous video # 72 spin drift unavailable?

@MWAdams605 5 жыл бұрын

Yes, what happened to video #72? Did it get pulled by the KZfaq thought police, like the reloading sections?

@arlo12345678910 9 жыл бұрын

Speaking from the northern hemisphere standpoint; It makes perfect sense why lateral deflection is to the right when shooting north and south, and also why vertical deflection is up or down when shooting east and west. However, I can't find any decent explanations why the lateral deflection is still to the right when shooting east and west. It seems the reasoning falls apart when applying it to E/W firing situations. I can appreciate that I must follow the physical laws if I want to achieve long rang accuracy but I long to understand why I must do it rather than, "because if you don't you'll miss" LOL

@arlo12345678910 9 жыл бұрын

OK I think i'm grasping it after reading all the other posts. Again from northern hemisphere standpoint; It's because of the spherical aspect of the earth. Because the target is not just moving toward or away it is always moving to the left. Depending upon direction of fire it is either climbing or dropping to the left. So on east west shots the projectile will hit high and right or low and right.

@JohnyBravo44 Жыл бұрын

There is NO horizontal definition shooting East to West or vice versa. The earth is either moving away from the bullet in flight or towards it in this scenario, hence Vertical correction exist only at those shooting directions. Of course if you are using combination of cardinal directions like SE to NW so shooting diagonally, you will get partial values of horizontal and vertical apparent drift. You would really need computer to calculate this like military artillery ballistics computer.

@spicychich1718 5 жыл бұрын

For those of you that were wondering where part 72 was I found right here in the link in internet archives. Not sure why it was made private (BS youtube guidelines or etc.). archive.org/details/youtube-v-LB6qwuDYs

@jimsagubigula7337 3 жыл бұрын

Thanks.

@Blake4Truth 10 жыл бұрын

New frame of reference terms to learn: angular: relating to rotational or spin component(s) of motion, and linear: relating to translational component(s) of motion. While the entire earth spins (angular motion) at the same rate, different points on the earth's surface may have different rates of linear translation. The speed of translation being directly proportional to the distance from the earth's axis of rotation.

@wmk0100 6 жыл бұрын

I may be misunderstanding, but wouldn't it matter more when shooting from north to south and south to north, which direction you correct. Not northern or southern hemisphere. The earth rotates in the same easterly direction no matter where you are.

@tbled52 10 жыл бұрын

Rex, i would be interested in a collection of all the formulas we may need. just so i could have a list in my shooting book/at my desk for reference. Can point me to has place that has them.

@cloudisunset 10 жыл бұрын

Horizontal drift makes sense shooting north or south but shooting east to west on same latitudinal line is tripping me out. Why does it appear to go right if target, FTP, and projectile were already traveling same speed?

@7071t6 3 жыл бұрын

Also lets not forget the projectile has its own gravitational field or exertion, its spinning at over 250,000 revolutions once it leaves the barrel either spinning to the right or to the left depending on the barrel and what you asked for and also the amount of the ratio you picked ie: 11 to 1 or 10 to 1 etc, that also becomes a factor?

@224ryder 4 жыл бұрын

Hey Rex, long time subscriber, I just wanted to bring it to your attention that Part 72 video is missing. I would think that you already knew that so is there any other way to get that information off that video? I know it is some important stuff and it has me at kind of a stand still right now. Thanks a lot buddy.

@KORMMM 4 жыл бұрын

archive.org/details/youtube-v-LB6qwuDYs

@224ryder 4 жыл бұрын

KORMMM Thanks a lot brother

@coovv685 2 жыл бұрын

where is part 72? i cant seem to find it

@ExON00 10 жыл бұрын

I figured it out, feel kind of stupid now. But it was kind of hard to visualize how the target seems to move in relation to a bullet in free flight over a sphere at any given angle. I'm at 70degrees North and at worst this will give me 2L @ 1000m. Thank you for all your work. I've been looking for a Ballistic Excel sheet for a long time. I love how I can format it and convert it how I wish. Not sure how I'll be able to apply my changes to new versions though, its a lot of work.

@seanmostert4213 6 жыл бұрын

Hi Rex, I’ve searched for Sniper 101 Part 72 because it didn’t play through from Part 71, and its not coming up in my search, has it been removed or something?

@spicychich1718 5 жыл бұрын

archive.org/details/youtube-v-LB6qwuDYs

@christkrebsbach325 5 жыл бұрын

The link you gave at the bottom to click on is all out of focus Rex. Enjoying your videos very informative .

@michaelalan6459 3 жыл бұрын

Rex, I do not know if you have addressed this but your video Sniper 101 part 72 that was to go over spin drift in greater detail is a "private video".

@cratxn1 9 жыл бұрын

@18:40 instead of the crosshair depiction in relationship to the bullseye, Rex should show a "Bullet" and its relationship to the bullseye. The target and the shooter's relationship ( even his POA ) have not changed, they are both on the earth's surface spinning together i.e. the same distance apart. The bullet is in free space while the target's relationship is being changed by the target apparently rising[ shooting to the West ].

@frankbeans289 5 жыл бұрын

Hello TRex...can you repost SNIPER 101 Part 72? Seems the lefties at KZfaq/Google made it "private".

@cratxn1 9 жыл бұрын

@19:02( i.e. shooting East ) the depiction should change from the crosshair in the first frame to a bullet and its relationship in subsequent frames i.e. the target falling away causing the POI to be high..Once again the POA through the scope does not change for the earth bound shooter fixed in relationship to his also earth bound target. The bullet's perspective is the one that varies while it is in free space. Muzzle to Target

@rexlee3710 5 жыл бұрын

I think the effect of shooting to the east and west is also known as the Eotvos effect which deals the change of centrifugal force on the bullet.

@Raymarr77 10 жыл бұрын

Crazy concept! Very informative video, thanks!

@CSNH375 6 жыл бұрын

part 72 isn't available?

@BobbyKindred 2 жыл бұрын

How can you have the same hours in a day at the top of the spinning ball that you do in the middle?

@kitcanyon658 2 жыл бұрын

What? Are you asking why everyone experience 24 hours to rotate back to the same position relative to the sun?

@awatt Жыл бұрын

Perspective.

@joeface530 5 жыл бұрын

What happened to video 72 on Spin drift tables?

@hpuxptus3018 5 жыл бұрын

archive.org/details/youtube-v-LB6qwuDYs enjoy

@nateg342 4 жыл бұрын

I am confused on one thing. I understand that when firing due North and due South in the Northern Hemisphere that the bullet will impact to the right, and in the southern hemisphere it will impact to the left, due to the fact that the target will be spinning faster or slower to where the firer pulls the trigger and releases the bullet. Happy with that. But what I don't understand is when Rex says at 16:42: "an interesting thing to note is that your horizontal correction, regardless of direction your shooting whether it be N, S, E or W.....its going to be the same amount of horizontal Coriolis correction." How is this possible if you are shooting directly east? The target would be on the exact same latitude as you are, therefore it is moving at the same speed to the east as you. I understand that your bullet would impact high and you would need to make a vertical correction, but how is it possible for the horizontal correction to be the same as the correction you would make if you were firing due N or S? Can someone please explain this to me? Thanks

@travf8020 3 жыл бұрын

Because the world does not spin on a perfect axis

@travf8020 3 жыл бұрын

Exceptional question

@stellan0r 5 жыл бұрын

Hey Rex, whats up with part 72?

@ACXB24 9 жыл бұрын

Curious if a bullet would even shift left to right on a target if you were shooing north or south. Wouldn't Newton's law on motion come into play then? I'm just thinking an object in motion stays in motion unless acted upon by an outside force. The bullet would already be in motion with the earth's rotation and wouldn't hit left or right because the target is rotating at the same speed as the bullet. I believe you mentioned both times you shot north and south the bullet hit to the right. Is it possible the weapon wasn't sighted in perfectly? If the earth acted on the bullet's left or right impact it'd have impacted left AND right, not right and right. Am I wrong? I'm not trying to argue, it just doesn't seem right to me

@dickchiggas1514 6 жыл бұрын

It confused me too a long time ago. But remember that the bullet as it travels down the barrel is receiving a horizontal force component due to the rotational speed of the earth at the location of the shooter. The "effect" really is a calculation or delta between the shooter and the target. That is why the bullet always moves to the right in the northern hemisphere. I see you asked this 2 years ago - my response is for new viewers.

@philippefrater2000 6 жыл бұрын

JSF No cause it's leaving contact with the Earth...

@kite4life 4 жыл бұрын

What happened to Part 72 ? :-(

@SeanWinkler 3 жыл бұрын

Is there a video showing these theories in action?

@jimsagubigula7337 3 жыл бұрын

Yeah, pretty much every shooting video over a kilometer.

@nathanyamaha465 3 жыл бұрын

Have you actually used and verified Coriolis effect in your long range shooting?

@TheRebelliousMeatPuppet 8 ай бұрын

So what do you think Rex? Flat or Globe? If it's flat it spins like a roulette wheel or Coriolis wouldn't be a thing.

@tiortedrootsky 7 ай бұрын

Horizontal coriolis for shooting north/south is about difference in distance travelled due to rotation for the shooter and the target. If Earth is a spinning disk, similar effect would be at place.