Long distance range and chronograph

[JDHasty]

Now that's right way to get data!

 I've shot with a lot of guys how've never shot over a chronograph but were leathal out to 5-600 yards just because they actually went out and shot.

They are not necessary, but we were wanting to validate the published BC and also the velocities published in reloading manuals back in the1980s and also just to entertain ourselves.  To calculate BC you do need a couple laboratory grade chronographs and also survey accurate distance between the chronograph screens.  You also needed walkie talkies or cellular phones and someone to hang out in the pit, but today a data connection is probable an affordable alternative. 

We would lace the screens on the Oehlers and shoot through to proof them and adjust screen spacing to zero them one against the other.  A magneto speed and an Oehler sounds accurate enough and far cheaper today.

Calculating BCs isn't really that complicated. I calculated the BC of the 160gr Matrix VLD using a $100 shooting chrony set up at 10' from the muzzle and then at 100 yards. My results were within .002 of the Litz BC. Shooting just doesn't need to be that much work

Of course they were, you are one of those special people who can load a batch of ammo that has velocity with standard deviation of < .002 //s//

That aside:
From Shooting Chrony's own web site:
Every SHOOTING CHRONYŽ measures the speed of bullets, arrows, shotgun & airgun pellets, paintballs, et cetera, from 30/fps. to 7000/fps. and with better than 99.5% accuracy.

So you are using an instrument with an error of < .005 and you need to take readings at two distances.

The precision of your results cannot, by definition, be any more precise than the least error of any of your measurements.

FWIW, the 99.5% accuracy is the average tolerance of their equipment. That doesn't mean every machine that comes off of the line is 99.5% accurate 100% of the time. My $100 chrony was just as consistent and as accurate as the Oehler 35P that I had before it. I sold the Oehler after buying the Shooting chrony because my results were so close between the 2 and the Oehler was such a pain to set up. I paid $250 for the 35P and sold it for $550 to some sucker just after they stopped producing them. I've never missed it. Even now I have a Magneto Speed and still use the beat up Shooting Chrony as well.

I've said it before and I'll say it again, shooting at any distance just isn't that tough. Handloading and getting accurate loads just isn't that tough. Getting single digit ES and SD velocities just isn't that tough. Shooting .25 MOA 3 shot groups at 100 yards isn't that tough. It doesn't require any technical back ground, special equipment, or shooter's voodoo. It just takes time, patience, and practice. Look how often people post on here showing sub .5 MOA groups with inexpensive guns shooting factory ammo. Equipment is getting so good these days that even affordable guns, ammo, optics and chronys will get you consistent and reliable results just as good as high dollar items.

Accuracy is a function that is a function of screen spacing.   Try again. 

The expected error on any one shot depends on both velocity and screen spacing. Typical errors are shown in the table.
1 FT, 2 FT, 4 FT, 8 FT


1000 FPS
5 fps 3 fps 1 fps 1 fps

2000 FPS
10 fps 5 fps 3 fps 2 fps

3000 FPS
16 fps 8 fps 4 fps 2 fps

4000 FPS
21 fps 10 fps 5 fps 3 fps

Furthermore to measure ballistic coefficient with ANY meaningful degree of precision the technique is to measure both initial velocity and final velocity of each fired round (using chronographs) over a measured range distance between the chronographs. Then today a software analysis program would be used to compute the ballistic coefficient value which would cause the standard bullet starting at the initial velocity to have a computed final velocity equal to the measured final velocity. The ballistic coefficient of a real bullet always is measured with respect to a specific standard drag function (G1, G7, etc.).

[jay.sharkbait]

Now that's right way to get data!

 I've shot with a lot of guys how've never shot over a chronograph but were leathal out to 5-600 yards just because they actually went out and shot.

They are not necessary, but we were wanting to validate the published BC and also the velocities published in reloading manuals back in the1980s and also just to entertain ourselves.  To calculate BC you do need a couple laboratory grade chronographs and also survey accurate distance between the chronograph screens.  You also needed walkie talkies or cellular phones and someone to hang out in the pit, but today a data connection is probable an affordable alternative. 

We would lace the screens on the Oehlers and shoot through to proof them and adjust screen spacing to zero them one against the other.  A magneto speed and an Oehler sounds accurate enough and far cheaper today.

Calculating BCs isn't really that complicated. I calculated the BC of the 160gr Matrix VLD using a $100 shooting chrony set up at 10' from the muzzle and then at 100 yards. My results were within .002 of the Litz BC. Shooting just doesn't need to be that much work

Of course they were, you are one of those special people who can load a batch of ammo that has velocity with standard deviation of < .002 //s//

That aside:
From Shooting Chrony's own web site:
Every SHOOTING CHRONYŽ measures the speed of bullets, arrows, shotgun & airgun pellets, paintballs, et cetera, from 30/fps. to 7000/fps. and with better than 99.5% accuracy.

So you are using an instrument with an error of < .005 and you need to take readings at two distances.

The precision of your results cannot, by definition, be any more precise than the least error of any of your measurements.

FWIW, the 99.5% accuracy is the average tolerance of their equipment. That doesn't mean every machine that comes off of the line is 99.5% accurate 100% of the time. My $100 chrony was just as consistent and as accurate as the Oehler 35P that I had before it. I sold the Oehler after buying the Shooting chrony because my results were so close between the 2 and the Oehler was such a pain to set up. I paid $250 for the 35P and sold it for $550 to some sucker just after they stopped producing them. I've never missed it. Even now I have a Magneto Speed and still use the beat up Shooting Chrony as well.

I've said it before and I'll say it again, shooting at any distance just isn't that tough. Handloading and getting accurate loads just isn't that tough. Getting single digit ES and SD velocities just isn't that tough. Shooting .25 MOA 3 shot groups at 100 yards isn't that tough. It doesn't require any technical back ground, special equipment, or shooter's voodoo. It just takes time, patience, and practice. Look how often people post on here showing sub .5 MOA groups with inexpensive guns shooting factory ammo. Equipment is getting so good these days that even affordable guns, ammo, optics and chronys will get you consistent and reliable results just as good as high dollar items.

Accuracy is a function that is a function of screen spacing.   Try again. 

The expected error on any one shot depends on both velocity and screen spacing. Typical errors are shown in the table.
1 FT, 2 FT, 4 FT, 8 FT


1000 FPS
5 fps 3 fps 1 fps 1 fps

2000 FPS
10 fps 5 fps 3 fps 2 fps

3000 FPS
16 fps 8 fps 4 fps 2 fps

4000 FPS
21 fps 10 fps 5 fps 3 fps

Furthermore to measure ballistic coefficient with ANY meaningful degree of precision the technique is to measure both initial velocity and final velocity of each fired round (using chronographs) over a measured range distance between the chronographs. Then today a software analysis program would be used to compute the ballistic coefficient value which would cause the standard bullet starting at the initial velocity to have a computed final velocity equal to the measured final velocity. The ballistic coefficient of a real bullet always is measured with respect to a specific standard drag function (G1, G7, etc.).

You going to give credit to the guys who wrote this?

Google can be your friend and enemy.

http://www.exteriorballistics.com/ebexplained/articles/the_ballistic_coefficient.pdf

http://www.oehler-research.com/custom/specs.html

[JDHasty]

Now that's right way to get data!

 I've shot with a lot of guys how've never shot over a chronograph but were leathal out to 5-600 yards just because they actually went out and shot.

They are not necessary, but we were wanting to validate the published BC and also the velocities published in reloading manuals back in the1980s and also just to entertain ourselves.  To calculate BC you do need a couple laboratory grade chronographs and also survey accurate distance between the chronograph screens.  You also needed walkie talkies or cellular phones and someone to hang out in the pit, but today a data connection is probable an affordable alternative. 

We would lace the screens on the Oehlers and shoot through to proof them and adjust screen spacing to zero them one against the other.  A magneto speed and an Oehler sounds accurate enough and far cheaper today.

Calculating BCs isn't really that complicated. I calculated the BC of the 160gr Matrix VLD using a $100 shooting chrony set up at 10' from the muzzle and then at 100 yards. My results were within .002 of the Litz BC. Shooting just doesn't need to be that much work

Of course they were, you are one of those special people who can load a batch of ammo that has velocity with standard deviation of < .002 //s//

That aside:
From Shooting Chrony's own web site:
Every SHOOTING CHRONYŽ measures the speed of bullets, arrows, shotgun & airgun pellets, paintballs, et cetera, from 30/fps. to 7000/fps. and with better than 99.5% accuracy.

So you are using an instrument with an error of < .005 and you need to take readings at two distances.

The precision of your results cannot, by definition, be any more precise than the least error of any of your measurements.

FWIW, the 99.5% accuracy is the average tolerance of their equipment. That doesn't mean every machine that comes off of the line is 99.5% accurate 100% of the time. My $100 chrony was just as consistent and as accurate as the Oehler 35P that I had before it. I sold the Oehler after buying the Shooting chrony because my results were so close between the 2 and the Oehler was such a pain to set up. I paid $250 for the 35P and sold it for $550 to some sucker just after they stopped producing them. I've never missed it. Even now I have a Magneto Speed and still use the beat up Shooting Chrony as well.

I've said it before and I'll say it again, shooting at any distance just isn't that tough. Handloading and getting accurate loads just isn't that tough. Getting single digit ES and SD velocities just isn't that tough. Shooting .25 MOA 3 shot groups at 100 yards isn't that tough. It doesn't require any technical back ground, special equipment, or shooter's voodoo. It just takes time, patience, and practice. Look how often people post on here showing sub .5 MOA groups with inexpensive guns shooting factory ammo. Equipment is getting so good these days that even affordable guns, ammo, optics and chronys will get you consistent and reliable results just as good as high dollar items.

Accuracy is a function that is a function of screen spacing.   Try again. 

The expected error on any one shot depends on both velocity and screen spacing. Typical errors are shown in the table.
1 FT, 2 FT, 4 FT, 8 FT


1000 FPS
5 fps 3 fps 1 fps 1 fps

2000 FPS
10 fps 5 fps 3 fps 2 fps

3000 FPS
16 fps 8 fps 4 fps 2 fps

4000 FPS
21 fps 10 fps 5 fps 3 fps

Furthermore to measure ballistic coefficient with ANY meaningful degree of precision the technique is to measure both initial velocity and final velocity of each fired round (using chronographs) over a measured range distance between the chronographs. Then today a software analysis program would be used to compute the ballistic coefficient value which would cause the standard bullet starting at the initial velocity to have a computed final velocity equal to the measured final velocity. The ballistic coefficient of a real bullet always is measured with respect to a specific standard drag function (G1, G7, etc.).

You going to give credit to the guys who wrote this?

Google can be your friend and enemy.

http://www.exteriorballistics.com/ebexplained/articles/the_ballistic_coefficient.pdf

http://www.oehler-research.com/custom/specs.html

Gee, I guess I better come clean.  I did not derive this information first hand I relied on the manufacturer, much like I would do if I were interested in the tow rating on my pickup and looked it up in the user's manual and I relied on the writings of an expert in exterior ballistics for the info on Drag Coefficient.  GTHOH. 

Where else would you go for the specifications on an Oehler chronograph?  FWIW, the specifications they have on their website are the same as what is in the printed user manual we have had since ~ 1987.  The info on Drag Coefficients was information I downloaded off a CD newsletter email I got from Sierra. 

[yorketransport]

Once again thank you guys for the advice! I am a bow hunter at heart but have found a new love of picking off yotes at a longer distance. I was shooting my 338 before I got this rifle and needless to say the coyotes didn't do too well against a 210 grain round! I don't load my own rounds so I have settle on the 75 grain horndy superformance witch has a listed mv of 3580 but out of my rifle (24" barrel) its at the 3550-3560 mark, not a huge difference but it's enough.

3550 fps with a 75gr bullet should do a real number on any coyote you see! And it should be significantly more pleasant to shoot than a 338.

Gee, I guess I better come clean.  I did not derive this information first hand I relied on the manufacturer, much like I would do if I were interested in the tow rating on my pickup and looked it up in the user's manual and I relied on the writings of an expert in exterior ballistics for the info on Drag Coefficient.  GTHOH. 

I guess that's where we differ. Instead of relying on the work of others I personally prefer to go out and get real world, hands on data like the OP did. All the ballistics research, software programs, theoretical models and internet searches in world can't hold up against practical, real world raw data.

When I was in college I worked as a tutor to help pay for school. More specifically I would work with high school students in math, physics, and chemistry classes. There were always those individuals who had all the book knowledge they could get but never applied it to the real world. Because of this they did great on tests but struggled when it came to lab work. Conversely, there were always a few students who initially showed little understanding of the text but did beautiful labs. The hands on students were without question better prepared and had much deeper knowledge of the subject matter than anyone who focused primarily book studies and parroting back the experience of others. While it's always important to read and understand the work of experts it's much more important to go out and gather raw data then sit back with an open mind and asses it without any preconceived view what the data should say. Relying on info from sources which are trying to take your money (Oehler, Brian Litz, or anyone else who provided info in exchange for compensation) is always risky behavior. They cannot be viewed as impartial observers. But if I go out and gather my own data using my own time and money I can compare it to the data derived from others and then make my own assessment.

The OP has learned more about his gun, load, shooting and ballistics with his hands on exercise than he ever will by listening to a bunch of internet experts (myself included). I should point out that I'm not really a reliable source for any information though, especially ballistics. My focus was more in kinematics and chemistry than ballistics in college.

[JDHasty]

Gee, I guess I better come clean.  I did not derive this information first hand I relied on the manufacturer, much like I would do if I were interested in the tow rating on my pickup and looked it up in the user's manual and I relied on the writings of an expert in exterior ballistics for the info on Drag Coefficient.  GTHOH. 

I guess that's where we differ. Instead of relying on the work of others I personally prefer to go out and get real world, hands on data like the OP did. All the ballistics research, software programs, theoretical models and internet searches in world can't hold up against practical, real world raw data.

[/quote]

What a clown.

I was discussing the ability to calculate the ballistic coefficients and the precision required to gather meaningful data for this purpose as well as the fact that in order to get meaningful data you must measure the same shot at two separated points downrange of the firing point. 

You are claiming that a shooting chrony is just as capable as a laboratory grade chronograph and when I show you that it is not you have a conniption because I provide the manufacturer's specifications and quote a ballistics engineer on the importance of the part drag coefficient plays.

In other words you are setting up a scenario in which the only way a person can comment on the accuracy of an instrument is to actually measure it and the only way a person can comment on exterior ballistics is to become a ballistician. 

You know I have had a belly full of you and your cohorts bullying and abuse and I am not alone in that regard.

Go jump in a lake. 

 

[JDHasty]

Furthermore, what I have witnessed from you and your merry band of cohorts is that anyone who has an opinion that disagrees with yours is met with ridicule, belittlement, piling on and other bully tactics. 

This is uncalled for and it is obvious that your designs are to shut down anyone who does not agree with you.

I could just not participate and/or keep my opinion to myself and I am fairly certain that that is what your designs are.  God only knows how many others you knotheads have driven off, but I am certain that there are more than a few people who no longer participate on this forum because of you and like minded individuals who are so disrespectful of others.     

[b23]

I think ya'll need to just hug it out.

[jay.sharkbait]

Furthermore, what I have witnessed from you and your merry band of cohorts is that anyone who has an opinion that disagrees with yours is met with ridicule, belittlement, piling on and other bully tactics. 

This is uncalled for and it is obvious that your designs are to shut down anyone who does not agree with you.

I could just not participate and/or keep my opinion to myself and I am fairly certain that that is what your designs are.  God only knows how many others you knotheads have driven off, but I am certain that there are more than a few people who no longer participate on this forum because of you and like minded individuals who are so disrespectful of others.   

Uhh, aren't you the guy who started the AR hunting thread? You know, the one that was a direct attack on Biggerhammer?

[Biggerhammer]

Ah hahahaha!

Yorke is far from a "Clown". I love the terms clown , idiot & monkey but none would apply to Yorke, unfortunately . If one was to read through Yorke's posts, one would come to the conclusion very quickly that he is in the "Know" a hands on "Been there done that" type. His posts are "Neutral and informative, derived from real world personal expirience. I've never had to read through the cut and paste murk when it comes to Yorke's straight up approach.

[JDHasty]

A third individual opened this discussion when he posted that published BCs are not always reliable especially with Nosler's published info.  I responded that we used our Oehler chronographs, back in the 1980s to verify the BC of some bullets and had fun doing so.  That is kind like "real world" experience, is it not?   

Accuracy of chronographs used for this sort of exercise came up in this thread and this: "I calculated the BC of the 160gr Matrix VLD using a $100 shooting chrony set up at 10' from the muzzle and then at 100 yards." was offered as a evidence that a pair of laboratory grade chronographs and survey quality distance measurement is not essential to calculating the BC of a bullet to .002  precision.

I am not saying that he did not get the result claimed, what I am pointing out is that a single event is not a verifiable and repeatable test and being able to get such results with a Shooting Chrony is not something anyone should have any confidence in simply because the measuring instrument does not allow that degree of precision.

What I state regarding the accuracy requirement of the instruments and screen spacing and distance between measurements is easily validated just by the fact that without this degree of accuracy a person cannot collect precise enough data to make these calculations.  That is a simple fact and it is intuitive.  Your results, by definition, cannot be any more precise that your least precise measured data. 

 

[jackelope]

Gee, I guess I better come clean.  I did not derive this information first hand I relied on the manufacturer, much like I would do if I were interested in the tow rating on my pickup and looked it up in the user's manual and I relied on the writings of an expert in exterior ballistics for the info on Drag Coefficient.  GTHOH. 

I guess that's where we differ. Instead of relying on the work of others I personally prefer to go out and get real world, hands on data like the OP did. All the ballistics research, software programs, theoretical models and internet searches in world can't hold up against practical, real world raw data.

What a clown.

I was discussing the ability to calculate the ballistic coefficients and the precision required to gather meaningful data for this purpose as well as the fact that in order to get meaningful data you must measure the same shot at two separated points downrange of the firing point. 

You are claiming that a shooting chrony is just as capable as a laboratory grade chronograph and when I show you that it is not you have a conniption because I provide the manufacturer's specifications and quote a ballistics engineer on the importance of the part drag coefficient plays.

In other words you are setting up a scenario in which the only way a person can comment on the accuracy of an instrument is to actually measure it and the only way a person can comment on exterior ballistics is to become a ballistician. 

You know I have had a belly full of you and your cohorts bullying and abuse and I am not alone in that regard.

Go jump in a lake.
[/quote]

These comments are completely uncalled for. This thread is locked.

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