Long Range Ballistics

It appears as though the difference is so small,it is only theoretical,and can't practically be measured.Unless of course you have a gun that groups small enough at 1000 yards to measure .2".

No doubt it is small but the greater the weight difference between the bullets the greater difference in deflection. The calculation is very complex and as you point out when comparing similar bullets the difference is small and likely the reason most ballistic programs don't include weight as a factor. When you actually look at what most ballistic programs offer, there are a lot of holes. My only point was that weight needs to be included for acurate calculation......

[elkhunter11]

I don't doubt it...few programs calculate wind properly.

Could you give us a link to a calculation that shows how to properly calculate wind drift.Preferably one that will show a difference that can actually be measured practically,unlike the JBM calculation that shows a difference of .2" at 1000 yards for a difference in weight of 20 grains(200gr vs 220 gr .308" bullet B.C. of .5 ,velocity of 3100fps as an example).If the JBM calculation is correct,I can see why most charts don't bother asking for the bullet diameter or the bullet weight.Nobody could possibly shoot groups tight enough to measure the difference,so for all practical purposes,it is insignificant enough not to bother with.

Originally Posted by elkhunter11

Could you give us a link to a calculation that shows how to properly calculate wind drift.Preferably one that will show a difference that can actually be measured practically,unlike the JBM calculation that shows a difference of .2" at 1000 yards for a difference in weight of 20 grains(200gr vs 220 gr .308" bullet B.C. of .5 ,velocity of 3100fps as an example).If the JBM calculation is correct,I can see why most charts don't bother asking for the bullet diameter or the bullet weight.

LOL...I doubt you'd find a calculator of that ability on line.

[elkhunter11]

The JBM calculation is found at the link that I posted,if someone really wants to calculate wind drift to an accuracy that they can't even measure by actual shooting.

[noneck180]

Mass and diameter have been used in the calculation of B.C....

[elkhunter11]

Mass is used in the calculation of B.C so if you are changing the weights..with out changing or unless you have a known B.C. of that bullet, from a previous formula,, the results will be skewed.

I was simply using different bullet weights,and entering the same B.C. and velocity to test the effect of bullet weight.The actual bullet does not have to exist for the purpose of the calculation.

[noneck180]

exactly ,, you are using numbers that are not real...

Can a .177 cal, 30gr bullet have a B.C of .700??? No


http://en.wikipedia.org/wiki/Ballist...icient#Formula

[Traps]

Originally Posted by sheephunter

LOL...I doubt you'd find a calculator of that ability on line.

Deflecting the question doesn't make you sound any smarter. The man asked you what your referencing, if you can't produce what you read or what your referencing, its just another useless opinion. And I'll throw in a LOL just to assert my position over you.

[elkhunter11]

exactly ,, you are using numbers that are not real...

Can a .177 cal, 30gr bullet have a B.C of .700??? No

Can a .308" bullet weighing 180gr have a B.C. of .500?

Can a .308" bullet weighing 200gr have a B.C. of .500?

Can a .308" bullet weighing 220gr have a B.C. of .500?

Those are realistic numbers,and those are the examples that I used.

Originally Posted by Traps

Deflecting the question doesn't make you sound any smarter. The man asked you what your referencing, if you can't produce what you read or what your referencing, its just another useless opinion. And I'll throw in a LOL just to assert my position over you.

Or you could buy a decent ballistic program and not be so rude!

[noneck180]

Elk,,

I realize you probably spent a day looking for your answers..I have moved on really..

[elkhunter11]

I realize you probably spent a day looking for your answers..I have moved on really.

Not at all,I just saw your post a few hours ago,then broke out laughing,because if you had read post #62,you would have seen that I used .308" 200gr and 220gr bullets,both with a B.C. of .500.I also used the 180gr bullet,but I never mentioned it in that post.

[noneck180]

yeah,,sure you did.. you can keep the thread going by yourself..

[switchsl]

I would be interested in seeing any formulas for wind drift calculations that anybody has, or did I miss them scrolling to fast. I would like to see somebody work through the equation too if you would.

[elkhunter11]

yeah,,sure you did.

Read post 62,and you will see why.If you don't see that my examples used .308" bullets of 200gr and 220gr with a B.C. of .500,read the post again,and again,until you do.

[noneck180]

Really its a guideline..if you are going to take these numbers to the bank go ahead..

[elkhunter11]

Really its a guideline..if you are going to take these numbers to the bank go ahead..

Weak comeback,very weak,I really expected a better attempt at a comeback from you after setting yourself up so well then catching yourself as a result.:

Nowhere did I post that I am putting my trust in the numbers.In fact,I even posted in post #62 that the differences were so small that they couldn't be verified by shooting.Perhaps you should read post #62 yet again.You set yourself up twice by not reading that one post.

[noneck180]

Elk,,

I don't know where your going,, but yes if the B.C is the same .. it will have the same affect on the bullet..but if a person was to purposely use wrong B.C.s in correlation to the weight in gr's..the formula means nothing..JC

[elkhunter11]

.but if a person was to purposely use wrong B.C.s in correlation to the weight in gr's..the formula means nothing.

Were the B.C.s that I used not realistic for those bullet weights?Before you answer,I did check several bullet makers sites before choosing those weights and B.C.s to use as an example.

[noneck180]

Elk,

again,,,I have never said that weight had anything to do with it..and as far as your B.C.s really I could care less,, because I only use Berger bullets...so if the point you are trying to get across that weight has nothing to do with it.. yup..
This is why for the most part long range shooters go for the heaviest bullet in that caliber, in a specific shape to give a better B.C...

[elkhunter11]

.so if the point you are trying to get across that weight has nothing to do with it.. yup..

The calculations clearly show that weight is such a small factor as to be insignificant,unless you call .2" less wind drift at 1000 yards significant.Can you even shoot groups tight enough at 1000 yards to show a difference of .2" of windage.

This is why for the most part long range shooters go for the heaviest bullet in that caliber, in a specific shape to give a better B.C...

Do they choose their bullets by weight,or by B.C.?They choose not to use even heavier for caliber bullets that could still be stabilized with reasonable velocities and twist rates,because such bullets would have a lower B.C..Therefore they obviously choose B.C. over weight.

[noneck180]

I just came to the conclusion..wait no awhile ago.. you like to type just to see what your thoughts look like typed out..JC..B.C does chit with out accuracy..and I answered Elkhunters daily Trivial Pursuit game a few posts ago.

[clakjp]

Originally Posted by elkhunter11

The calculations clearly show that weight is such a small factor as to be insignificant,unless you call .2" less wind drift at 1000 yards significant.Can you even shoot groups tight enough at 1000 yards to show a difference of .2" of windage.



Do they choose their bullets by weight,or by B.C.?They choose not to use shorter,even heavier for caliber bullets that could still be stabilized with reasonable velocities and twist rates,because such bullets would have a lower B.C..Therefore they obviously choose B.C. over weight.

If the bullets are the same design The weight does matter to get your better B.C. You are not compairing apples to apples. Also if you gun does not have the proper twist I guess you aint going to pick the heaviest bullet right?

I have read this from the get go. So what is your point??
What do you want to know??

[elkhunter11]

and I answered Elkhunters daily Trivial Pursuit game a few posts ago.

You proved that your reading comprehension is sorely lacking when you messed up trying to be sarcastic twice because you failed to comprehend the information in post #62.

So obviously,you failed to provide the correct answers.

SH is probably laughing as much as I am as he reads this thread.

[noneck180]

done

[elkhunter11]

I have read this from the get go. So what is your point??
What do you want to know??

I already know what I needed to know,trajectory is decided by B.C. and velocity,and out to 500 yards,a heavier bullet offers no advantage as far as trajectory is concerned.

As far as wind drift is concerned,for all practical purposes,it is also determined by velocity and B.C..The effect of weight is so slight as to offer no difference than can be measured by actual shooting.

[noneck180]

done

[clakjp]

Originally Posted by elkhunter11

I already know what I needed to know,trajectory is decided by B.C. and velocity,and out to 500 yards,a heavier bullet offers no advantage as far as trajectory is concerned.

As far as wind drift is concerned,for all practical purposes,it is also determined by velocity and B.C..The effect of weight is so slight as to offer no advantage than can be measured by actual shooting.

I use JBM ballistic software aswell and you are not correct.I does matter.I think you are doing somthing wrong.I was shooting today and my 168gr berger with a B.C. of .617 vers my 50 gr sierra with a B.C. of .243 sure made a difference at 500 yards. and 600 even worse. Like I stated in last post you are not compairing apples to apples.Also I think you have no clue on this topic.

[elkhunter11]

what I was saying is that you can put any B.C you want , wieght means nothing..but why would you do that??

Isn't it obvious?It was pointed out by Sheephunter that many ballistics charts and calculations,use a simplified wind drift calculation that doesn't take bullet weight into account.I was curious as to the actual effect of weight on wind drift,so I found a ballistic calculation that includes weight as well as velocity and B.C. to determine wind drift.I then entered a few different REALISTIC weights for a given velocity and B.C. and compared the results.There is in fact a difference in wind drift if you enter the bullet weight,but it is so miniscule that there is no practical way to even prove if the calculations are true by shooting.

By doing the sample calculations myself,I simply verified that bullet weight is not worth considering when calculating windage.Velocity and B.C. are for all practical purposes,the only factors other than the wind strength and direction, that matter.

[noneck180]

Originally Posted by elkhunter11

You proved that your reading comprehension is sorely lacking when you messed up trying to be sarcastic twice because you failed to comprehend the information in post #62.

So obviously,you failed to provide the correct answers.

SH is probably laughing as much as I am as he reads this thread.

So where did I say weight had anything to do with it?? before you rudely asked your type of questions many posts ago.
Just a note,, I can comprehend just fine..and I want an answer...no games.