Range Report Spindrift Calculation??

[Lowlight]

Re: Spindrift Calculation??

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Rifles Only</div><div class="ubbcode-body">The winds never got higher than a normal spring day. No new data with that.</div></div>

You only say that cause I am out of ammo for the 7WSM... if we had a working 300WM you could shoot it in the hurricane,

but alas, we have no working 300WM, only 300MW ammo.

Besides Lisa emailed me you were scared of the rain.

Personally I think you are fine with rain, it's wind over 35MPH that scares you.

 

[Rifles Only]

Re: Spindrift Calculation??

Ok. you are right. The wind that high messes up my hair.

However, The data would only be interesting with the 308.

 

[Lowlight]

Re: Spindrift Calculation??

You have very nice hair there Leif, I wouldn't want to see it mussed up.

Harbinger is good to go, you can get that wet... just be sure to clean it when you are done.

 

[Rifles Only]

Re: Spindrift Calculation??

If you ever use the "C" word again, I am gonna hang you from a tree in a tac vest and leave you there...

not really, I just like to talk big shit

 

[MitchAlsup]

Re: Spindrift Calculation??

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Brown Dog</div><div class="ubbcode-body">But, no argument. You're absolutely right. ..But what you've described would only enable 3 DOF modelling and takes no account of the orientation of the projectile itself –and, therefore, no account of the changing forces acting upon it. </div></div>

By knowing that the effect of wind is 'linear in time' but the effect of spindrift is 'quadradic in distance':

The clever numerical analysist can extract the spin drift from the x,y,z;time dataset (and also windage). That is the physicist has already limited the problem by the definitions of the various effects, leaving the NA to figure out how to extract desired data and how to measure how accurately this data is represented.

<div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body">To genuinely model (spin) drift you must either have 4 DOF (one additional axis longitudinally through the projectile) or 6 DOF (ie also gather x,y,z data on the movements of projectile itself -in addition to the 3 DOF data defining where it is in space)</div></div>

There's no doubt that higher precision measurements, or more measurements in general, yield higher precision results, and that (well constructed) models with higher degrees of freedom more accurately respresent the physics that actually takes place.

 

[NOBODY]

Re: Spindrift Calculation??

Again,this is ripe for opportunity.

"What about doubling twist rate?

Will a 1-7" .224 require double "spin drift" correction at 1000yds,over a 1-14" at same?"

 

[TiroFijo]

Re: Spindrift Calculation??

NOBODY, it will not double but it will be different. It is not linear. The exact amount is difficult to calculate and it will depend a lot on the particular bullet/load used.

Perhas some member has data on spin drift of the M193 load in 1:12 vs 1:7 barrels.

 

[NOBODY]

Re: Spindrift Calculation??

I shoot both and often...but perhaps I was lucky enough to always score self correcting erectors?(grin)

 

[okiemnmm]

Re: Spindrift Calculation??

Interestin-
There have been several students who have attempted 1000 yards with various 223s. Any twist slower than 1-10" struggled to get as far as 600 yards much less 1000. Bullets it could stabilize dunt do well enough to call a group n bullets designed to go LR keyholed at 100 yards so no tellin where they went once ya try for 600.

Thinkin someone is in over their head, though that really doesnt take alot of depth now does it

 

[TiroFijo]

Re: Spindrift Calculation??

NOBODY, as many have said before the amount of spin drift at 600 yds is negligible, and even at 1000 yds is easily lost in minute wind changes and difficult to notice. But it is there...

what is the 224 with a 1-14 twist that you shoot at 1000 yds?

 

[Brown Dog]

Re: Spindrift Calculation??

Mitch, I have a feeling we're (sort of) agreeing.

With 3 DOF doppler data you can approximate your drift observations for a particular firing with, perhaps, a simple algorithm.

If it's particularly important, you can better that by modelling different sections of the drift with a series of best fit algorithms;

but what you won't get is the ability to model anything other than that proj at that mv at that stability factor.

ie it won't read across to any other bullet / spin / mv combination ...other than as an approximation ....well, an approximation of an approximation!


So back to what (I think!) the thread started out about:

I would, from my educated standpoint

, contend that no handhelds are calculating (spin) drift. They are approximating it.



As to the 'no point, it's lost in the noise' argument....I'm at a loss!

How hard is it to calculate your deflection at (say) 1000m and then take 3 clicks off?!

The actual issue is that most people don't have that simple data on their tables

 

[Lowlight]

Re: Spindrift Calculation??

Isn't it lost in the noise by the fact no ones windage includes it as far as tables.

if I need 10MOA in the wind to hit an 12" wide target at 1000, and I pull .75 off, isn't that a miss... cause i sure as heck hit already with the wind my tables give me without clouding it with SD.

My Math maybe off as I am throwing that out there off the cuff, but if no tables are calculating for it, isn't that asking for a problem ?

And if the answer is take it off, why am I putting it on the in the first place ?

 

[jwp475]

Re: Spindrift Calculation??


The chart put up by someone earlier in this thread is for artillery rounds and not shoulder fired rifles. Also if one is useing a VLD very high BC bullet that exhibits SD then they will need to shoot it themselves and measure it on a very clear and calm day.
I think that most that think they have SD don't have thier scopes level and are dialing in windage as they dail in elevation.

AS I stated earlier with no wind I don't use any SD correction and I am hitting center mass on windage

 

[Lowlight]

Re: Spindrift Calculation??

Well I know several years of shooting all different locations I have never shot alongside anyone who used it and they all still managed to hit well. I never noticed one competitor at any of our annual matches use it either, but I could be mistaken.

Also, I still contend it's different for a zeroed rifle compared to a PBZ'd rifle, which I think is were the problem comes into play.

I know I watched Jeff Badley make a first round hit in West VA on a 1997 yard target with a 7WSM and he didn't use it, George, Myself and Jeff were the top 3 guys using nearly identical dope, no one ever mentioned 3 xtra clicks of anything and we shot past 1000 yards... maybe I'm just a left leaner.

No wind to measure it, well good luck with that.

 

[jwp475]

Re: Spindrift Calculation??



Mr. Lowlight you are spot on in my experience...

 

[Brown Dog]

Re: Spindrift Calculation??

Lowlight,

I'm not here as a 'drift evangelist'. If you don't want to use it; don't. Simple

-although I would ask what you would do when using something such as the cheytac ABC that gives you the drift -would you switch that functionality off?!

jwp,

The table posted was for a 155 scenar. Most people know that's 308. Apologies if you thought that meant 155mm. I would have thought that was a mistake not easily made.

 

[Lowlight]

Re: Spindrift Calculation??

Well seeing how I never, ever, shoot in a no wind situation I would probably just use the windage it gave me as I wouldn't use "two" numbers.

As well, I have absolutely zero interest in buying or using the Chey Tac system. I have a palm with a Horus chip, a PDA with FFS , Patagonia, and Nightforce EXBAL, so i think am I covered. And the easiest one of the bunch, the least robust in my opinion gets me a tons of 1st round hits out to 1000 yards.... so anything else these others do is gravy.

For the record I simply don't use it and chuckle at people who shoot inside 1000 yards who do... especially after they zeroed at 100.

Which, you may not be the SD Evangelist we think you are, but you are a pretty strong advocate who questions people who believe it is "noise"... which you never answered my question, how does this relate to a rifle zeroed at a given range versus a rifle with a PBZ... that has yet to be answered from the witch doctors with their 3 click cure to better shooting.

 

[NOBODY]

Re: Spindrift Calculation??

Mike D,

I'm all ears on the 223 that won't reach 1K.

A transonic slip is an issue seperate from "spindrift" and I'm sure your "vast experience" coincides a hard right turn at the slip,due to spindrift.

Take a calm day,shoot at a slight downhill angle into water and note the "spindrift" affects,in conjunction with the slip.

Keep flapping your gums and talking out your ass about shit you've never seen or done...that commentary is riveting.

Give or take.

 

[TiroFijo]

Re: Spindrift Calculation??

LL, the SD at 100 yds is almost zero, so why the comment:
"I simply don't use it and chuckle at people who shoot inside 1000 yards who do... especially after they zeroed at 100"?

A close range zero (100 or 200 yds) have nearly ZERO imput of SD, so you still have to correct nearly the full value of it at long ranges.

If you have never seen SD that's OK, I think most people have never seen it because nobody really knows what the wind is doing downrange.

 

[jwp475]

Re: Spindrift Calculation??



Brown Dog, perhaps if you level your reticle so as not to be dialing in windage with each elevation correction your spin drift will go away.
Are perhaps you are have the same problem a friend of mine had. He claimed to have 2 1/2 MOA of spin grift at 500 meters, but a very carefull inspection of his rifle revealed a bent barrel. A bit of straighting and his "spin drift" went away magicaly.


You posted this and sincew it specifficaly mention artillery

[/quote]

 

[jwp475]

Re: Spindrift Calculation??

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: TiroFijo</div><div class="ubbcode-body">LL, the SD at 100 yds is almost zero, so why the comment:
"I simply don't use it and chuckle at people who shoot inside 1000 yards who do... especially after they zeroed at 100"?

A close range zero (100 or 200 yds) have nearly ZERO imput of SD, so you still have to correct nearly the full value of it at long ranges.

If you have never seen SD that's OK, I think most people have never seen it because nobody really knows what the wind is doing downrange. </div></div>

If you cann't see it then why bother?

975 yards <span style="font-style: italic"> <span style="text-decoration: underline">no spin drift correction </span> </span>

Looks pretty close to center, also the target is only 10" wide and some are dialing in 10"+ at 1K If I did that I could not hit my <span style="font-style: italic"> <span style="text-decoration: underline">target at all </span> </span>

 

[TiroFijo]

Re: Spindrift Calculation??

jwp475, I think I´ve seen the same picture as your example a few times already in this same thread...

So, are you absolutely CERTAIN there was no wind? If so, don't dial SD.

But that still does not mean there is no SD. Are you CERTAIN your scope level is perfect, as well as the turret tracking?

I think we are all repeating ourselves.

 

[jwp475]

Re: Spindrift Calculation??



Yea I'm fairly certain that my scope is tracking properly.

If my scope reticule was not level when adjusting elevation then the windage would not stay in the middle of the target at varying ranges

How about this at 975 yards and again no spin drift correction

Appaerently Lowlight and the guy's that he shoots with don't adjust SD either

 

[Andrew Blubaugh]

Re: Spindrift Calculation??

I recently purchased some 175 grain BTHP/GSS (boat tailed hollow point gyro scope stabalizing) rounds. These rounds have a tiny gyro scope inside that eliminates spin drift.

I can do a group buy for these if you guys want? Maybe we can do a dual group buy for these and some beach front property I am selling in Colorado, Arizona and Iowa.

 

[jwp475]

Re: Spindrift Calculation??

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: cowboy_bravo</div><div class="ubbcode-body">I recently purchased some 175 grain BTHP/GSS (boat tailed hollow point gyro scope stabalizing) rounds. These rounds have a tiny gyro scope inside that eliminates spin drift.

I can do a group buy for these if you guys want? Maybe we can do a dual group buy for these and some beach front property I am selling in Colorado, Arizona and Iowa. </div></div>


I like a little comedy....

 

[Lowlight]

Re: Spindrift Calculation??

TF, nobody is saying it doesn't exists, it most certainly does... however to the amount it's beyond the range of most peoples accuracy to hold or recognize appears to be truer statement.

the "no wind factor" is the most important fact when you consider just how difficult it is to know what the wind is doing downrange, exactly like you said.

So, if the drift is there, but small, if a 1 MPH wind trumps the amount of drift at 1000 yards, as well as most people's inherent accuracy behind a rifle at that distance, then it should be clear to anyone reading its "noise"?

Instead we have people advocating the addition of SD correction at ranges from 600 yards and beyond, if not from the start.

 

[jwp475]

Re: Spindrift Calculation??

You are spot on IME. As you posted ealier your shooting buddy made a hit at 1997 yards with a 7 WSM with no SD correction and that says it all IMHO. If people can't deduct the facts from that then I am at a loss

 

[Shady_Jay]

Re: Spindrift Calculation??

http://www.youtube.com/watch?v=CMwdAc1Dzfg

 

[jwp475]

Re: Spindrift Calculation??

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: TiroFijo</div><div class="ubbcode-body">jwp475, I think I´ve seen the same picture as your example a few times already in this same thread...

So, are you absolutely CERTAIN there was no wind? If so, don't dial SD.

But that still does not mean there is no SD. Are you CERTAIN your scope level is perfect, as well as the turret tracking?

I think we are all repeating ourselves. </div></div>


Did you miss this post?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Lowlight</div><div class="ubbcode-body"><span style="font-weight: bold">Well I know several years of shooting all different locations I have never shot alongside anyone who used it and they all still managed to hit well. I never noticed one competitor at any of our annual matches use it either, but I could be mistaken.</span>

Also, I still contend it's different for a zeroed rifle compared to a PBZ'd rifle, which I think is were the problem comes into play.

I<span style="font-weight: bold"> know I watched Jeff Badley make a first round hit in West VA on a 1997 yard target with a 7WSM and he didn't use it, George, Myself and Jeff were the top 3 guys using nearly identical dope, no one ever mentioned 3 xtra clicks of anything and we shot past 1000 yards... maybe I'm just a left leaner. </span>
No wind to measure it, well good luck with that.

</div></div>

 

[Louis Corkern]

Re: Spindrift Calculation??

Good Day,

Well seems this thread has come full circle and back almost to where it began lol.
Of everyone that posted their opinions and experience of why some dont figure for spin drift is LL. If you zero your rifle for 200, 300, 400, etc then your "zero" already has that distances spin drift accounted for it. Example:
100yd zero in no wind then you already account for spin drift
200yd zero in no wind then you already account for spin drift
So on out to whatever distances you desire to shoot. Think about it for a minute...look in your data books and notice difference of windage adjustment count for your zero at each distance you have. Does your 900 or 1200yd zero have no windage adjustment click from your 100yd zero? And what direction are those zeroed adjustments?

Now fast forward to PBZ and you have not taken into account the distances spin drift due to your zero nor have you had wind, etc been taken into consideration for the distance zeros.
If you are a PBZ person (which I only suggest if you are planning on going 1500m+) then yes you will have to account for spin drift at even the closer distances due to your "zero" has not taken it into account yet.

Thanks

 

[Brown Dog]

Re: Spindrift Calculation??

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Lowlight</div><div class="ubbcode-body">TF, nobody is saying it doesn't exists, it most certainly does... </div></div>

I think the fellow with the photos is arguing that it doesn't exist

As I said, If your cards don't have it; don't use it.

I stick to my point; naysayers decry it <span style="font-weight: bold">because they don't have the data on their cards</span>.


Let's not lose sight of the fact that the original post was asking how to calculate it - not 'should I shouldn't I?'

and then of course the thread is confused by low bandwidth individuals who keep popping up with Monty Pythonesque determination; screeching 'it doesn't exist, it doesn't exist'.

Speaking of which;

jwp,

I simply can't be arsed to explain this any more; if your level of ballistic understanding is such that you think a tube fired spin stabilised artillery projectile acts under different Laws of Physics to a spin stabilised bullet then you will never be able to conceptualise any of this...your posts here -and on LRH clearly demonstrate your lack of scientific knowledge and inability to argue from any theoretical standpoint other than <span style="font-weight: bold">what you think </span> 'Shawn told me' (which given his level of understanding certainly means you failed to understand his explanations) or 'ring Mr Perry' to find out what you misunderstood from him too? As the maxim goes 'empty vessels make the most noise'.

 

[jwp475]

Re: Spindrift Calculation??

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Brown Dog</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Lowlight</div><div class="ubbcode-body">TF, nobody is saying it doesn't exists, it most certainly does... </div></div>

I think the fellow with the photos is arguing that it doesn't exist

As I said, If your cards don't have it; don't use it.

I stick to my point; naysayers decry it <span style="font-weight: bold">because they don't have the data on their cards</span>.


Let's not lose sight of the fact that the original post was asking how to calculate it - not 'should I shouldn't I?'

and then of course the thread is confused by low bandwidth individuals who keep popping up in with Monty Pythonesque determination screeching 'it doesn't exist, it doesn't exist'.

Speaking of which;

jwp,

I simply can't be arsed to explain this any more; if your level of ballistic understanding is such that you think a tube fired spin stabilised artillery projectile acts under different Laws of Physics to a spin stabilised bullet then you will never be able to conceptualise any of this...your posts here -and on LRH clearly demonstrate your lack of scientific knowledge and inability to argue from any theoretical standpoint other than <span style="font-weight: bold">what you think </span> 'Shawn told me' (which given his level of understanding certainly means you failed to understand his explanations) or 'ring Mr Perry' to find out what you misunderstood from him too? As the maxim goes 'empty vessels make the most noise'.
</div></div>


I know for a fact that artillery adjust for spin drift. For you to take a personal shot at my intelegence and to say that learning from Mr. Peryy is meaningless shows your total lack of understnding in learning. Everyine learned from someone, inluding you.If real world shooting shows one no need to adjust for spin drift then why do it?

I guess that you also missed this post


<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Lowlight</div><div class="ubbcode-body"><span style="font-weight: bold">Well I know several years of shooting all different locations I have never shot alongside anyone who used it and they all still managed to hit well. I never noticed one competitor at any of our annual matches use it either, but I could be mistaken.</span>

Also, I still contend it's different for a zeroed rifle compared to a PBZ'd rifle, which I think is were the problem comes into play.

I<span style="font-weight: bold"> know I watched Jeff Badley make a first round hit in West VA on a 1997 yard target with a 7WSM and he didn't use it, George, Myself and Jeff were the top 3 guys using nearly identical dope, no one ever mentioned 3 xtra clicks of anything and we shot past 1000 yards... maybe I'm just a left leaner. </span>
No wind to measure it, well good luck with that.

</div></div>

From what I have seen from the info that you posted (10+ inhes of spin drift correction for a 30 Cal 155 grain bullet) I would certainly take the word of Shawn and Gerald Perry of Pery Systems over your BS

 

[TiroFijo]

Re: Spindrift Calculation??

Just my opinion, but I think a first shot hit at 2000 yds without taking into account SD is nothing but sheer luck...

check this:
http://www.snipershide.com/forum/ubbthreads.php?ubb=showflat&Number=572656#Post572656

Note JL and his buddies has access to extensive radar data for the 338 LM thanks to their finnish military connections. After all Finland is the home of the 338 LM.

On page 4: "Spin drift surely affects. If I recall right, for 2000 m I used spindrift correction left 1,6 mrad" ...that's 5.5 MOA at 2000 m or about 10.5 feet.

A 1.0 mph wind error is "only" worth about 1.6 MOA at this range, so the spin drift is about equal to missing your wind call by 3.4 mph. Quite significant.

Of course in LL's example it was a 7mm WSM at 1997 yds, it is not going to be the same value but you get the idea

 

[jwp475]

Re: Spindrift Calculation??

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Later</div><div class="ubbcode-body">Good Day,

Well seems this thread has come full circle and back almost to where it began lol.
Of everyone that posted their opinions and experience of why some dont figure for spin drift is LL. If you zero your rifle for 200, 300, 400, etc then your "zero" already has that distances spin drift accounted for it.<span style="font-weight: bold"> Example:
100yd zero in no wind then you already account for spin drift
200yd zero in no wind then you already account for spin drift
So on out to whatever distances you desire to shoot. Think about it for a minute...look in your data books and notice difference of windage adjustment count for your zero at each distance you have.</span> Does your 900 or 1200yd zero have no windage adjustment click from your 100yd zero? And what direction are those zeroed adjustments?

Now fast forward to PBZ and you have not taken into account the distances spin drift due to your zero nor have you had wind, etc been taken into consideration for the distance zeros.
If you are a PBZ person (which I only suggest if you are planning on going 1500m+) then yes you will have to account for spin drift at even the closer distances due to your "zero" has not taken it into account yet.

Thanks </div></div>


I tend to agree with that line of thinking..

 

[Louis Corkern]

Re: Spindrift Calculation??

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: jwp475</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Later</div><div class="ubbcode-body">Good Day,

Well seems this thread has come full circle and back almost to where it began lol.
Of everyone that posted their opinions and experience of why some dont figure for spin drift is LL. If you zero your rifle for 200, 300, 400, etc then your "zero" already has that distances spin drift accounted for it.<span style="font-weight: bold"> Example:
100yd zero in no wind then you already account for spin drift
200yd zero in no wind then you already account for spin drift
So on out to whatever distances you desire to shoot. Think about it for a minute...look in your data books and notice difference of windage adjustment count for your zero at each distance you have.</span> Does your 900 or 1200yd zero have no windage adjustment click from your 100yd zero? And what direction are those zeroed adjustments?

Now fast forward to PBZ and you have not taken into account the distances spin drift due to your zero nor have you had wind, etc been taken into consideration for the distance zeros.
If you are a PBZ person (which I only suggest if you are planning on going 1500m+) then yes you will have to account for spin drift at even the closer distances due to your "zero" has not taken it into account yet.

Thanks </div></div>


I tend to agree with that line of thinking..</div></div>


So does your 1200yd known zero have no windage adjustment clicks from your 100yd zero? And if it does what direction do they seem to be?

 

[jwp475]

Re: Spindrift Calculation??



I'll try to get out to 1200 tomorrow if possible and see what happens

 

[Brown Dog]

Re: Spindrift Calculation??

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: jwp475</div><div class="ubbcode-body">From what I have seen from the info that you posted (10+ inhes of spin drift correction for a 30 Cal 155 grain bullet) I would certainly take the word of Shawn and Gerald Perry of Pery Systems over your BS
</div></div>

Fick meine alte Stiefel

,

They would <span style="font-weight: bold">agree</span> with me.

<span style="font-weight: bold"> You</span> don't understand what <span style="font-weight: bold">they</span> are saying.



Take some time to educate yourself; the Palma 'rule of thumb' is 1 MOA at 1000.

err, what's that in inches?

 

[Lowlight]

Re: Spindrift Calculation??

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: TiroFijo</div><div class="ubbcode-body">Just my opinion, but I think a first shot hit at 2000 yds without taking into account SD is nothing but sheer luck...

check this:
http://www.snipershide.com/forum/ubbthreads.php?ubb=showflat&Number=572656#Post572656

Note JL and his buddies has access to extensive radar data for the 338 LM thanks to their finnish military connections. After all Finland is the home of the 338 LM.

On page 4: "Spin drift surely affects. If I recall right, for 2000 m I used spindrift correction left 1,6 mrad" ...that's 5.5 MOA at 2000 m or about 10.5 feet.

A 1.0 mph wind error is "only" worth about 1.6 MOA at this range, so the spin drift is about equal to missing your wind call by 3.4 mph. Quite significant.

Of course in LL's example it was a 7mm WSM at 1997 yds, it is not going to be the same value but you get the idea

</div></div>

Well you keep upping the ante, let's talk a 1000 yards, and in this case the 1 MPH wind there with a 308. If you want to qualify it by going to 2000m, that my friend is a completely different story all together.

Which is why I qualified my comments to shooting 1000 yard cause we all know things start to change dramatically after that...

 

[Brown Dog]

Re: Spindrift Calculation??

Lowlight,

I'm going to bow out of this shortly, it's going nowhere.

Before I do; out of interest, do you actually have any drift data for your rounds?

To reject something out of choice is one thing;

To reject it because you haven't got the data -or the people who trained you didn't have it- is another.

 

[Lowlight]

Re: Spindrift Calculation??

I'm pretty sure the data I had gave me .67 MOA at 1000 yards, and frankly, I find that number pretty useless.

As I said, numerous times, I don't shoot in "No Wind" conditions and cannot think of a single place I have shot that would qualify as such, and I shoot all over the country. Maybe you missed it early, I have just about every ballistic program out there, and some add this gem called SD into the equation if you want, but its so small why bother.

In my experience I have seen far more issue with changing winds than anything that requires a .67 adjustment at that distance.

Recently I was practicing at Byers Field in Colorado, using a 260 and <span style="font-style: italic">(only)</span> a 10" plate at 1000 yards, <span style="font-style: italic">(I moved off paper after 600 yards)</span> and I had no problem repeating hit after hit at that distance and any misses could 100% be attributed to wind.

I find working in the real world and reading the current conditions far more valuable than running numbers in order to add in an adjustment that is beyond most people's capabilities. Show me a shooter who can consistently hold .7MOA or less at a 1000 yards and I will concede they probably should be considering it... however if they're a .7MOA shooter at that distance why bother.

 

[Brown Dog]

Re: Spindrift Calculation??

I understand entirely what you're saying.

Once you've shot the errors out, and are repeatedly hitting a target, knowing what amount of that error was drift is irrelevant.

However, when you're prepping for your very 1st shot, it's generally appropriate to wish to make it absolutely the best shot you can.

Ignoring drift in that situation is little different to deciding to ignore a quantifiable pressure or temp change ......and simply waiting to shoot the error out based on observation of the first shot.

That's fine if that's what you choose or have to do....

.but, when opportunity allows, it's nice to know you've given that first shot your very best effort

 

[Lowlight]

Re: Spindrift Calculation??

it's true, however everything I do, and everything I have that helps me make that first hit, especially with consideration to the wind does not take that into account. And I am not paying for the ABC software...

My first rounds hits are respectable, but honestly, rather than sticking .6 on the rifle, i would rather work the wind as best I can because at the end of the day that is what makes the real difference. No amount of SD can correct a bad wind call.

Range, Wind, Fundamentals... if I can succeed at that, the rest will sort itself out just fine.

 

[Rifles Only]

Re: Spindrift Calculation??

TF. No disrespect. Finland is not the home of the 338. Only where it became commercialized

 

[jwp475]

Re: Spindrift Calculation??



Brown Dog, Lowlight ignores spin drift to 1K and that's ok because as you say it works for him.

I ignore spin drift and hit what I am shooting at and you can my intelegence into question.

I hope that one day we can continue this discussion in person eye to eye.

 

[Lowlight]

Re: Spindrift Calculation??

At this point I'd let it go... I think has been beat, and beat severely with a stick, aluminum bat, mace... you get the picture.

 

[Shady_Jay]

Re: Spindrift Calculation??

does it go left in the Southern Hemisphere?

 

[The Mechanic]

Re: Spindrift Calculation??

left is Kalifornia right is New Jerk or Basterdchusetts

 

[jsarcher]

Re: Spindrift Calculation??

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Captain Kick-Ass</div><div class="ubbcode-body">does it go left in the Southern Hemisphere?
</div></div>

Not if you're shooting South/East/West........

 

[Brown Dog]

Re: Spindrift Calculation??

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: jwp475</div><div class="ubbcode-body">

I hope that one day we can continue this discussion in person eye to eye. </div></div>



Not clear if that's a piece of keyboard hono(u)r/bravado pish or a genuine statement

.

If the former; ho hum.

If the latter; err, unlikely

.

 

[TiroFijo]

Re: Spindrift Calculation??

Jacob, I know the story of the 338 LM:
http://en.wikipedia.org/wiki/.338_Lapua_Magnum

It was originally an american wildcat that was not fully developed and was dropped, and it was Lapua of Finland and AI (UK) and Sako (Finland) rifles that put it on the map, and are the most widely used SWS in the world in this caliber. The Lapua lock base 250 gr FMJ bullet is AFAIK the first (and only?) NATO listed.

Perhaps is semantics: place of birth is USA but "home" to me is Finland