Wind Drift vs Velocity by BC

[Guest]

You sure did.

I made that chart and I understand it. Yes if you don't understand the math and you only take what is on that chart, you MIGHT come to that conclusion.

Bob and I were talking about the sweet spot in velocity for pellets and I believe the point being made was that there is a velocity at which the pellet is MORE EFFICIENT at flying. That discussion (which I believe took place on airgunguild) convinced me that pellets flying between about 840 and 880 or so are right where they will perform best. I started studying the effect and during that study I made that table. Bob Sterne and I were in agreement (I believe). There is a "sweet spot" where you get the "optimum" performance meaning BC is highest for the pellet.

That DOES NOT preclude the idea that one pellet of one side section may be more susceptible to drift than another of a different section. So what CAN and DOES SOMETIMES HAPPEN is this. A pellet which has a large side cross section can have a better BC than another pellet and at the same time be drifted more by the wind THAN THE EQUATIONS PREDICT because there is no compensation in the math (typically) which addresses the susceptibility of a specific pellet to drift. The drift which is calculated is FOR the MODEL not for the pellet under test.

Now I don't want anyone to think that Bob agrees with the assertion I am making here. We did not talk about that. Ask him if you want his opinion of what I am trying to explain here. If I am wrong it won't be the first time I have had to thank him for straightening me out.

Now look, take this argument to someone YOU TRUST. You don't trust me so TAKE IT TO SOMEONE YOU TRUST.

 

[Franklink]

Now look, take this argument to someone YOU TRUST. You don't trust me so TAKE IT TO SOMEONE YOU TRUST.

No need to take to anyone. I actually shoot at far enough distances to have seen exactly what your chart shows. And what chairgun and strelok and any other ballistic app shows. Higher BC = less wind drift. 

(Although it would be interesting to see what Mr. Sterne has to say about your claim that BC isn't a decent predictor of a pellets ability to resist getting pushed in the wind). 

 

[Guest]

My friends,

let's not get this thread also shut down.

I found the discussion on the thread I posted rather interesting — before we drifted off into something less airgunny....



Let's move on to things that will help airgunning.

One suggestion: Help airgunners make a gun purchase or tuning decision of how much power they want in a gun and what caliber.

To make an informed decision we could offer them charts that show how beneficial additional power truly is to (1) increase point blank range, (2) offset typical ranging errors, and (3) offset wind drift of typical wind estimation errors. All these charts would differentiate between typical calibers (and using typical quality, high BC pellets).



Peace,

Matthias

Don't worry Matthias, that's not going to happen here. One of us has already been corrected today and I fully intend to take that correction to heart. Still the information he wants is important TO HIM as well as simply important to other shooters.

 

[Guest]

Now look, take this argument to someone YOU TRUST. You don't trust me so TAKE IT TO SOMEONE YOU TRUST.

No need to take to anyone. I actually shoot at far enough distances to have seen exactly what your chart shows. And what chairgun and strelok and any other ballistic app shows. Higher BC = less wind drift. 

(Although it would be interesting to see what Mr. Sterne has to say about your claim that BC isn't a decent predictor of a pellets ability to resist getting pushed in the wind).

I don't think that is a claim I made, but I might have.. But it would be interesting to have his opinion upon the claim I am making. I am not going to write it down for you again. Go back, reread. You will figure out exactly what I am trying to explain.

That data is "notional" it reflects the inherent biases of the ballistics model which is in Chairgun (and any assumptions the author made). I do not propose to know what those are but every model has them. That data does not tell us anything specific about the relationship to the GA drag model and any specific pellet. It can't I was not looking at a pellet. I was looking at the model itself and TBH the evidence for that is above in this thread @centercut posted in the thread as did others who brought in some of Bob's graphs (which are brilliant) to help us all understand what is happening at those velocities.

Honestly, go get his thinking I am ALWAYS willing to be corrected, no matter how much I might get emotionally involved in a subject. Maybe Bob can explain to me why we don't have something like a BC which is used to refine wind drift relative to the model projectile. Maybe your right. Maybe that coefficient is somewhere in the math and I have just never understood it.

Either way, you and I are at an impasse and you are no longer interested in what I am saying so ... yeah. That's where we are. Find an expert you respect.

The point of that table is THIS Faster ain't always better.:

 

[Franklink]

Now look, take this argument to someone YOU TRUST. You don't trust me so TAKE IT TO SOMEONE YOU TRUST.

No need to take to anyone. I actually shoot at far enough distances to have seen exactly what your chart shows. And what chairgun and strelok and any other ballistic app shows. Higher BC = less wind drift. 

(Although it would be interesting to see what Mr. Sterne has to say about your claim that BC isn't a decent predictor of a pellets ability to resist getting pushed in the wind).

I don't think that is a claim I made, but I might have.. 

..I am ALWAYS willing to be corrected..

The point of that table is THIS Faster ain't always better.:

Well here's some correction, 

"BC is not intended to have ANY relationship what so ever to wind drift" 

That's a straight quote from you in the thread that got locked. So, yes, you MIGHT have said that.

When you shared this table you were trying to make the point that faster isn't better, which is sometimes true (as an example, an MRD @ 950+ can have a pretty incredible BC). So there are exceptions. What your table also shows, as also seen in real world shooting, high BC pellets drift less in wind than low BC pellets. Simple. 

 

[Guest]

Now look, take this argument to someone YOU TRUST. You don't trust me so TAKE IT TO SOMEONE YOU TRUST.

No need to take to anyone. I actually shoot at far enough distances to have seen exactly what your chart shows. And what chairgun and strelok and any other ballistic app shows. Higher BC = less wind drift. 

(Although it would be interesting to see what Mr. Sterne has to say about your claim that BC isn't a decent predictor of a pellets ability to resist getting pushed in the wind).

I don't think that is a claim I made, but I might have.. 

..I am ALWAYS willing to be corrected..

The point of that table is THIS Faster ain't always better.:

Well here's some correction, 

"BC is not intended to have ANY relationship what so ever to wind drift" 

That's a straight quote from you in the thread that got locked. So, yes, you MIGHT have said that.

When you shared this table you were trying to make the point that faster isn't better, which is sometimes true (as an example, an MRD @ 950+ can have a pretty incredible BC). So there are exceptions. What your table also shows, as also seen in real world shooting, high BC pellets drift less in wind than low BC pellets. Simple. 

BC does not perfectly model wind drift. It is not intended to do that. It has a very strong relationship yes. Wind drift is calculated from time of flight. A high BC reduces time of flight therefore wind drift a low BC increases time of flight therefore wind drift. Neither thing directly reflects the side on cross section of the pellet. AFAIK there is nothing in the equations which compensates for a pellet with a large "sail" area. If there is, by all means show it to me. Hence my suggestion you contact someone whose opinion you actually want.

Yes high BC pellets almost always drift less in the wind than lower BC pellets. You can not say that is ALWAYS true.

Does that work for you?

 

[Franklink]

Yes high BC pellets almost always drift less in the wind than lower BC pellets. You can not say that is ALWAYS true.

Does that work for you?

Yep, that'll do. 

(I'd still like to see you roll up to a long range airgun competition to test your theory of small side profile projectiles and wind drift against pellets that have actually proven to be the best we currently have at long range accuracy and precision ).

 

[Guest]

Yes high BC pellets almost always drift less in the wind than lower BC pellets. You can not say that is ALWAYS true.

Does that work for you?

Yep, that'll do. 

(I'd still like to see you roll up to a long range airgun competition to test your theory of small side profile projectiles and wind drift against pellets that have actually proven to be the best we currently have at long range accuracy and precision ).

Take the good with the bad... I also said...

"BC does not perfectly model wind drift. It is not intended to do that. It has a very strong relationship yes. Wind drift is calculated from time of flight. A high BC reduces time of flight therefore wind drift a low BC increases time of flight therefore wind drift. Neither thing directly reflects the side on cross section of the pellet. AFAIK there is nothing in the equations which compensates for a pellet with a large "sail" area. If there is, by all means show it to me. Hence my suggestion you contact someone whose opinion you actually want."

That invite isn't ever going to happen although I did hit a golf ball at 150 yards once with my D460. It did take seven tries though. But you are welcome to drag out a spring rifle and try the ten dimes challenge I might be real impressed. Here is your target.

Ten Dimes Challenge Targets

 

[Therealld]

Now look, take this argument to someone YOU TRUST. You don't trust me so TAKE IT TO SOMEONE YOU TRUST.

No need to take to anyone. I actually shoot at far enough distances to have seen exactly what your chart shows. And what chairgun and strelok and any other ballistic app shows. Higher BC = less wind drift. 

(Although it would be interesting to see what Mr. Sterne has to say about your claim that BC isn't a decent predictor of a pellets ability to resist getting pushed in the wind).

I like to test various ammo in a gun I plan to use for a certain purpose, I have shot literally hundreds of different airguns and know some shoot certain model pellets more accurately than others, (I know pointed pellets don’t perform as well as similar roundheads etc.) but yet some pellets don’t get it done at longer ranges unless they have a rounder head shape and are longer and heavier ... its sometimes a tradeoff, but because I can retune many guns to shoot better at longer ranges, I find the charts, though useful for starters, I find some barrels shoot at high velocity with less wind drift than others, and some tunes give better results with respect to drift too, so the same pellet at the same launch speed can vary downrange.

I never look at bc charts or drift charts in lieu of test firing the setup I’m working on downrange for effect. That said, I do often use my Labrador setup during testing too.

I feel hunting GAME with airguns at extreme ranges is unethical, but am ok sortof with it in pesting situations IF the “first shot” kill rate is over 70percent of so, which it rarely is. Charts can make a hunter take shots he isnt practiced enough at.

 

[Guest]

It's just a chart. The point of the chart was immediately gleaned, as if by magic, by the first replier.

If you don't know your ability and limits with a specific rifle you have no business shooting at live targets with it at any range.

Can you link the fish and game department that told you one shot kill rates are less than 70 percent?

 

[Therealld]

It's just a chart. The point of the chart was immediately gleaned, as if by magic, by the first replier.

If you don't know your ability and limits with a specific rifle you have no business shooting at live targets with it at any range.

Can you link the fish and game department that told you one shot kill rates are less than 70 percent?

I have seen a lot of hunting and can very confident that ALL airgun hunting at very long ranges, if studied honestly, will reveal less than 70% first shot kill rates.

I don’t need the authorities to dictate my mores and conscience with respect to hunting, and don’t believe in magic. True many DO reason that if its not forbidden by law its ok, and I don’t recall hunting regulations limiting appropriate shooting distances, but its not my way to ignore my own findings and experience regarding hunting.

With respect to long range shooting, I feel that 70% chance is in a range of good sense where most shots would be “hit the mark” under hunting conditions. Airguns are generally most suitable for small game hunting, and most small game have effective kill zones between a nickel and a fifty cent piece.

My own shooting under controlled conditions has taught me that shooting really good airgun/pellet combos at the same aimpoint will usually deliver deliver inch groups at 50 yards if over thirty shots are in the group, yet a series of a few five shot groups might be closer to a half inch per group. Yet my observations are that very few airgunners can hit a fifty cent piece from field positions (prone is most steady) reliably beyond about 50-60 yards. 

I see some bragging about 200+yard hunting with airguns but opine any real success included “sighters and “firing for effect” (misses and woundings woundings). I used to love to hunt, and shot thousands of groundsquirrels back in the day (mostly with rimfires, but lots with airguns too) and I didn’t feel bad with woundings because they were pests predating farmer’s fields, but even so, most shots we took were within high probability distances. From decent rests from seated position with “target type” scopes and rifles capable of moa accuracy.

 

[Guest]

It's just a chart. The point of the chart was immediately gleaned, as if by magic, by the first replier.

If you don't know your ability and limits with a specific rifle you have no business shooting at live targets with it at any range.

Can you link the fish and game department that told you one shot kill rates are less than 70 percent?

I have seen a lot of hunting and can very confident that ALL airgun hunting at very long ranges, if studied honestly, will reveal less than 70% first shot kill rates.

I don’t need the authorities to dictate my mores and conscience with respect to hunting, and don’t believe in magic. True many DO reason that if its not forbidden by law its ok, and I don’t recall hunting regulations limiting appropriate shooting distances, but its not my way to ignore my own findings and experience regarding hunting.

With respect to long range shooting, I feel that 70% chance is in a range of good sense where most shots would be “hit the mark” under hunting conditions. Airguns are generally most suitable for small game hunting, and most small game have effective kill zones between a nickel and a fifty cent piece.

My own shooting under controlled conditions has taught me that shooting really good airgun/pellet combos at the same aimpoint will usually deliver deliver inch groups at 50 yards if over thirty shots are in the group, yet a series of a few five shot groups might be closer to a half inch per group. Yet my observations are that very few airgunners can hit a fifty cent piece from field positions (prone is most steady) reliably beyond about 50-60 yards. 

I see some bragging about 200+yard hunting with airguns but opine any real success included “sighters and “firing for effect” (misses and woundings woundings). I used to love to hunt, and shot thousands of groundsquirrels back in the day (mostly with rimfires, but lots with airguns too) and I didn’t feel bad with woundings because they were pests predating farmer’s fields, but even so, most shots we took were within high probability distances. From decent rests from seated position with “target type” scopes and rifles capable of moa accuracy.

You and I are almost in complete sync on this then. That is why I said, "If you don't know your ability and limits with a specific rifle you have no business shooting at live targets with it at any range."

Personally I think shooting ground squirrels at 200 yards with a high end PCP and some "boolit" (why do AG people always make up these silly names?) is almost universally inhumane and should be done only if you can't use something like a 22 Hornet or 17 rimfire. Such tools are far superior to a $2000.00 rifle mounting a $1000.00 optic and cost about a third as much at the high end. Hit that GS with that 40 gr spitzer BT steaming along at 2 grand and he never feels a thing. Shoot him through the gut with that anemic 40 gr "boolit" now barely making 700 800 fps and the poor gutshot bastard crawls in a hole and spends a hour, or a day or two dying... Probably just me and my prejudices but yeah.

I totally agree with you that airguns are decidedly not a good tool for that sort of pest removal EXCEPT where there is no other alternative.

See there, we can agree.

That said, I would not judge the guys who enjoy pesting with those tools. There are no doubt plenty of places where that tool is the safest tool for that job.

In my recollection I have only taken around ten shots at living critters at ranges over 50 yards with my Condor (only once ever with a spring rifle) and in all cases it was ground hogs, in town where I WANTED them to go into their holes and expire. I took one shot on a squirrel at 79 yards with my John in Pa tuned D48 mounting an ATN X-sight. Boom! head shot but that was really pushing it and I have never tried it again. I've taken two squirrels at 55 yards with my Stormrider. That's it. That's all the small game I have ever even shot at beyond 50 yards with an airgun. I would advise ANYONE interested to follow that example, some will, some will know their limits and decide that they can push that out there.. more power to them if they are being responsible.

 

[JungleShooter]

Does anybody have any opinion on the 70% kill rate being appropriate to be ethical, too low, or higher than necessary?

For pests — or game — or both?

For DRT-kills — or R&D-kills and F&D-kills (run & die, fly & die kills)?



Matthias

 

[Guest]

Does anybody have any opinion on the 70% kill rate being appropriate to be ethical, too low, or higher than necessary?

For pests — or game — or both?

For DRT-kills — or R&D-kills and F&D-kills (run & die, fly & die kills)?



Matthias

Sir, with respect, I believe every hunter should keep that percentage well above 95%. That's the hunting perspective I have. Every shot should result in a humane kill. We owe that to our prey. Sometimes there are factors which demand a loosening of that level of respect for our quarry, and for the guys doing pest work, I know, you have pests which need removing and you are going to do that as humanely as you possibly can. I guess, Matthias, because I know your heart, if the hunter walks away from the shot feeling it could have been better then it was a shot he should not have taken. If a hunter walks up to a kill, and does not thank God and feel respect for the life he has taken, he probably should take up some other activity. It's in your heart. I know you know these things ... Ohana bra.

 

[Therealld]

I never said, or implied airguns should ONLY be used for hunting in situations where there is no other alternative. I enjoy hunting with firearms and even moreso with airguns, and see nothing wrong with that. But I go along with the ancient tradition of recovering any GAME you shoot.

I have airguns I tested in perfect conditions from the bench that delivered occasional 0.5 moa at 50yards sometimes missed half the 55 yard 2” targets in a Field Target match the next day due to miss-judging wind, mis-ranging, and match jitters or or whatever. I know few hunters are as well-prepared equipment-wise or as practiced for such shooting as seasoned Field Target shooters.

 

[Guest]

I never said, or implied airguns should ONLY be used for hunting in situations where there is no other alternative. I enjoy hunting with firearms and even moreso with airguns, and see nothing wrong with that. But I go along with the ancient tradition of recovering any GAME you shoot.

Neither did I say that. I agree with your ancient tradition. There are situations though when there is no other alternative. AGs are most effective in those situations. What I said was that the shooter should know what he can do with the equipment he has and decide accordingly.

I have airguns I tested in perfect conditions from the bench that delivered occasional 0.5 moa at 50yards sometimes missed half the 55 yard 2” targets in a Field Target match the next day due to miss-judging wind, mis-ranging, and match jitters or or whatever.

I've seen that sort of thing, how in the world did that do that? Little gust of wind... a quakey between you and the deer (archer's will know the term)... Yeah.

I know few hunters are as well-prepared equipment-wise or as practiced for such shooting as seasoned Field Target shooters.

This right here demonstrates an awful lot of "confidence" which may or may not be justified by experience. I have known (most have passed) a lot of men and some women who would eat while you and I starved and they never shot a paper target in their lives... never left a carcass in the field and never wasted a bullet (because thirty six cents for a box of long rifles was literally a couple of hours work). I imagine you remember 18 cents a gallon for gasoline. 

FTT is a wonderful sport. I really wish I had taken it up when I was younger. I know you are older than me and still doing it. I admire that. I used to shoot field target archery. It prepares you to shoot, yes. It does not teach you much at all about hunting. There's "well prepared" and there's "well prepared". 

If you know how to set a snare, your kills may not always be humane but you will always eat.

 

[bandg]

I never said, or implied airguns should ONLY be used for hunting in situations where there is no other alternative. I enjoy hunting with firearms and even moreso with airguns, and see nothing wrong with that. But I go along with the ancient tradition of recovering any GAME you shoot.

Neither did I say that. I agree with your ancient tradition. There are situations though when there is no other alternative. AGs are most effective in those situations. What I said was that the shooter should know what he can do with the equipment he has and decide accordingly.

I have airguns I tested in perfect conditions from the bench that delivered occasional 0.5 moa at 50yards sometimes missed half the 55 yard 2” targets in a Field Target match the next day due to miss-judging wind, mis-ranging, and match jitters or or whatever.

I've seen that sort of thing, how in the world did that do that? Little gust of wind... a quakey between you and the deer (archer's will know the term)... Yeah.

I know few hunters are as well-prepared equipment-wise or as practiced for such shooting as seasoned Field Target shooters.

This right here demonstrates an awful lot of "confidence" which may or may not be justified by experience. I have known (most have passed) a lot of men and some women who would eat while you and I starved and they never shot a paper target in their lives... never left a carcass in the field and never wasted a bullet (because thirty six cents for a box of long rifles was literally a couple of hours work). I imagine you remember 18 cents a gallon for gasoline. 

FTT is a wonderful sport. I really wish I had taken it up when I was younger. I know you are older than me and still doing it. I admire that. I used to shoot field target archery. It prepares you to shoot, yes. It does not teach you much at all about hunting. There's "well prepared" and there's "well prepared". 

If you know how to set a snare, your kills may not always be humane but you will always eat.

I agree completely. Quite a difference in shooting at static targets with time to range for distance and hunting which may never present the same. Admittedly, I've never tried Field Target but I'm confident that in past years I hunted as much as any here.