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Measuring BC - Oehler '89

Buford Boone

Private
Minuteman
Dec 4, 2003
28
30
61
Tuscaloosa, Al.
Having seen recent information on the Oehler System ’89, I thought I’d get a bit more out there for those that may have interest.

Disclaimer: I don’t work for Oehler Research. I’m good friends with Dr. Oehler and have used his equipment for many years. Any work I’ve done with Oehler Research has been voluntary. I’m not posting as a salesman.

I have wanted this technology for a long time. I volunteered my time and ammunition to do most of the beta testing on this system. I believe it is mature and works well.

What is it? - A system capable of giving very accurate Time of Flight and velocity measurements.

How much does it cost? - $2,985.00

Who is it for? - Those that desire to measure external ballistic performance of their system(s), particularly for ELR shooting.

Does it work in supersonic or subsonic range? - Either/both.

How far has it been tested? - 2 miles.

Does it require power? - It is battery powered and wireless between the gun and target units.

The Oehler System ’89 is not for everyone. You can go to the range and use Weaponized Math and get everything you need for shooting 100 - 1,000 yards. Nope, the ’89 won’t help you if that is what you want to do.

If you are not planning on shooting past about Mach 1.2 or if you are a rimfire guy and you don’t plan to shoot past 100 yards, it also probably won’t be of much help to you.

If, however, you are one of those that has made use of one of Bryan Litz’s excellent CDMs or PDMs, you probably could benefit from being able to measure future changes in your system.

I have run the ’89 simultaneously with Doppler Radar. When both are setup properly, they give the same avg. muzzle velocity and BC number for the range that the ’89 is deployed. The big difference in data is that radar gives you numbers for the entire flight of the bullet. The ’89 only gives you MV and a TOF to one distance. The TOF given by the ’89 includes the effect of drag over the entire flight. Make that distance the farthest you plan to shoot and use a drag function that is a good fit to your bullet and you have good data for everything in between.

A recent development is the community’s appreciation of SD of BC. We’ve understood for a while the importance of a low SD of MV. Little thought has been given to the SD of BC. Many people didn’t even consider that BC might change shot-shot and gun-gun. I believe the reason it has been ignored is that very few could actually measure it. Kind of like asking someone if they wanted to shoot over your chronograph and they would say “Why, the velocity is printed right on the box of ammunition”. That sounds funny today but I remember when it was a common response.

The Oehler ’89 will give you a velocity and BC number for every shot. It will give you an avg. and SD of both MV and BC for a group of shots. I’ve done a group as large as 100 shots.

Best part about SD of BC is that you don’t have to have a long range to measure it. For most centerfire cartridges, about 300 yards will do.

Want an accurate BC number to shoot far away? You must measure far away. Simply want to measure SD of BC? 300 yards is sufficient.

The ’89 will also give pure TOF measurements. That means you can run another type of chronograph to measure MV if you don’t want to bother with SkyScreens and long spacings. If you choose that route, you’d need to calculate the BC for every shot yourself. The ’89 includes a Stepped BC calculator that makes it pretty easy.

When measuring by bullet impact, MV, BC, AJ and shooter ability all play a part. Since the ’89 measures MV and BC and not impact location, none of those things influence the results.

No, it is not for everyone. Neither are chronographs. It is the first instrument I’m aware of that has this capability in this price range. The predecessor to this would do the same measurements but cost about $18k and was more difficult to operate.

The ability to measure TOF and, therefore, BC certainly answers some questions. The best part, though, is that it creates more questions than it answers. Want to know if modifying a bullet (tipping, nose ring, etc) helps with SD of BC? Yep, the ’89 will do that.

I always thought using a G1 for subsonic rimfire was the way to go. I tested the ammo at 100, 200 and 500 yards. I got different G1 numbers. I recomputed (don’t have to reshoot) under G7 and got the same number for all three distances. The G7 was the best fit over the velocity range of the subsonic ammo! Who would have thought that?

Imagine all the questions, and therefore answers, that will happen as more shooters gain this ability.

My hope is that this technology will advance our sport. If you believe posting this info on other forums will help, feel free to do so.

There are a few of these systems out there. A manufacturer of bullets that are well known in the ELR world has had a system for a couple of years. If you have experience with this system, I encourage you to add to the conversation with your thoughts.

Note to Mods: Permisison to post this was requested and approved by Lowlight.
 
Interesting! So if I send you some bullets what would it cost for you to measure the BC of them?
 
Interesting! So if I send you some bullets what would it cost for you to measure the BC of them?
Depending on how many you wanted tested and the time it would take to create loads then actually do the testing, it would likely cost more than purchasing an '89 so you could test them yourself.

I'd be happy to discuss with you and offer some recommendations. I'll try sending you contact info in a pm.
 
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I'd also like to add that there are a few '89s out there already. If one of the users reads this, he may be willing to test BC just for the opportunity to see your bullets and get more familiar with the system.
 
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Interesting! So if I send you some bullets what would it cost for you to measure the BC of them?
That depends on if I have a cartridge that will shoot them. Then loading, etc. I'm with Buford, buying one will be cheaper. ;-)
 
Cool thanks for the reply. I’m using 30 cal, 308 specifically. And am theorizing at the moment but will be turning some bullets very soon.
One other thing to think about is that if someone else tests them you will only know what they do in THAT person's rifle. They may not show the same performance in YOUR rifle(s).

Think of it like you would think of asking someone to shoot your loads for velocity. You would be far better off buying a chronograph and measuring velocity in your rifle than sending loads to someone to test in their rifle.
 
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We will likely be picking up an 89 soon.

Fairly unrelated, is there any better documentation for the 85 system? The website doesn’t have much about it.

Will be reaching out to oehler, but always like to read as much as possible first.
 
We all chase a high BC, and why wouldn't we? One of the most important things most overlook is the consistency of the BC. Long ago, I thought BC was a static number. I got it from the manufacturer and it was what it was. The same number was appropriate for everyone, for every shot. Modern measurements have shown that is not the case.

I once tested a .308 bullet with a G7 of .397. That sounds like a great bullet. In the 10 shots I fired, the lowest BC was .379. The highest BC was .412. There was no correlation to velocity and BC, the high and low were only 12 fps apart.

How could anyone expect to hit anything at distance with that much BC variation?

Yeah, I wondered why it had so much variation but that is more a question for the engineers that make bullets. I had enough info to know that I didn't want to use those bullets.

I sent the information to the manufacturer and he didn't reply. I looked him up at the SHOT Show and he dismissed me with "My bullets are tested on radar". I broke eye contact and walked away. My suspicion is that he didn't trust data from an unknown person and didn't realize that BC varied shot-to-shot. I really can't blame him. Very few people knew it at that time.

Bryan Litz has done a wonderful job of getting the word out on BC variation. He has done/is doing a great service in taking his radar around and creating PDMs for people. The ability for the enthusiast to make similar measurements will advance the science behind long range shooting.

Thru conversations with others about this, I got a great quote (the author can out himself if he wants): Truth Passes Through Three Stages: First, It Is Ridiculed. Second, It Is Violently Opposed. Third, It Is Accepted As Self-Evident.

Fun times!
 
Using the JBM Ballistic Coefficient (Time) calculator and my Labradar trace file it seems to provide a BC very close to the factory number.
Bullet was a Berger 140 Hybrid.

Dont know how accurate the results are it depends on how accurate the Labradar numbers are.

Anyone try this?

What were your results



1647635741392.png


1647635809890.png



Trace File
Time (s)Vel (fps)Dist (yd)SNR
0​
2775.25​
0​
-
0.114021​
2633.44​
102.68​
9.01​

 
We just received our 89, though haven’t had a chance to get it to the range yet to test with. Our Infinition Doppler radar will arrive in May and I will be able to test them side by side.

I will likely have both systems available for free BC testing prior to some of the WPRSC matches this year for any Great Lakes shooters that are interested.

I find it terribly disheartening that there is a major bullet designer that doesn’t know who you are and would blow you off Buford. I hope you will be presenting at the SAAMI conference this year as it was great hearing about your testing at the last one.
 
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Using the JBM Ballistic Coefficient (Time) calculator and my Labradar trace file it seems to provide a BC very close to the factory number.
Bullet was a Berger 140 Hybrid.

Dont know how accurate the results are it depends on how accurate the Labradar numbers are.

Anyone try this?

What were your results



View attachment 7830322

View attachment 7830323


Trace File
Time (s)Vel (fps)Dist (yd)SNR
0​
2775.25​
0​
-
0.114021​
2633.44​
102.68​
9.01​
For .22 LR it is very accurate.
For typical supersonic rifle projectiles it will be a bit high for an average as we are measuring a short distance. But the result is well within the range of typical BC truing; "adjust the middle number a digit or two."

Another forum member @ptosis made this online calculator that can measure an average and remove invalid tracks from multiple trk files giving an even better result:
 
Whatsupdoc said: Dont know how accurate the results are it depends on how accurate the Labradar numbers are.

The LabRadar machines have shown to be capable of giving very good numbers. If I run two and get the same (or very close) numbers, I trust them. I've had issues with muzzle blast or recoil bumping them out of alignment. When that happens, I simply realign them so that they agree and march on. Having said that, any calculation of a BC based on a LabRadar track should be very accurate. The limiting factor would be range. If you track a bullet to 100 yards and calculate a BC based on that track, you should have a great number for shooting...100 yards. Yeah, it should work a little farther but a good rule on measuring BC is to measure at the farthest distance you plan to shoot.

I tried to figure out a way to use a LabRadar to get a far downrange velocity but couldn't figure it out. Then I asked the folks at LabRadar and they said "Nope, it won't do that".

White_Shark: Thanks for the compliments on my presentation at the SAAMI Conference. I'll see you at this year's. It is great that you got an '89 AND have a Infinition on the way. You'll be able to do a lot of work with both.

If you have questions on using your '89, don't hesitate to hit me up.

Thanks, to all, for the conversation.
 
I heard an Oehler '89 was at the KO1M match and that people shot over it to get data to use.

If anyone knows, did the data match up with shooting the match? I know my experience has been the data is spot on but it would be interesting to know the experiences of others.

At White_Shark, sorry but I won't see you at the SAAMI Conference next week. I'll be doing a training class for some Lads. Did you get your Infinition?
 
I heard an Oehler '89 was at the KO1M match and that people shot over it to get data to use.

If anyone knows, did the data match up with shooting the match? I know my experience has been the data is spot on but it would be interesting to know the experiences of others.

At White_Shark, sorry but I won't see you at the SAAMI Conference next week. I'll be doing a training class for some Lads. Did you get your Infinition?

We did get our infinition, haven’t had a chance to test with the 89 side by side yet. We just moved into our new building, so decided to pass on the conference this year with everything else going on. I should be able to get the 89 and radar out sometime later this month.
 
I heard an Oehler '89 was at the KO1M match and that people shot over it to get data to use.

If anyone knows, did the data match up with shooting the match? I know my experience has been the data is spot on but it would be interesting to know the experiences of others.

At White_Shark, sorry but I won't see you at the SAAMI Conference next week. I'll be doing a training class for some Lads. Did you get your Infinition?
Yes it matched up very well according to the shooters I ran through. I interviewed most of the shooters after the match, all were happy and some matched to the click at all distances. It seems to be extremely accurate. Also did some limited testing on my Ko2m gun as well , BC attained from 1000 yards matched up amazingly well out to 3400 yards. So far I have tested the unit out to 2800 yards and still had a full signal strength as well.

Tim in TX
 
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Most here probably know but to the new users I would suggest when testing with the Infinition Radar or the Oehler 89 that all testing be done in a cross wind direction as close to full value as possible to get the really accurate reads for TOF data especially at the longer ranges . We tested the 89 today in 3-14 mph 6 o"clock tail winds today which I do not ever do normally for testing the vertical components of shots , but today I did not have a choice , The winds were steady and changing slowly enough to cherry pick the wind speed conditions to get some 1000 yard reads and get data as to the effects of the tail wind measurements at least. A Berger 407 measured with a 14 mph tail wind the BC 10 shot averages were .542 , in a 3-4 mph tail wind the BC averaged .517, close to zero tail wind averaged .507 , actual was .498 trued on AB with this particular rifle in a dead calm.

Tim in TX
 
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Yes it matched up very well according to the shooters I ran through. I interviewed most of the shooters after the match, all were happy and some matched to the click at all distances. It seems to be extremely accurate. Also did some limited testing on my Ko2m gun as well , BC attained from 1000 yards matched up amazingly well out to 3400 yards. So far I have tested the unit out to 2800 yards and still had a full signal strength as well.

Tim in TX
Good to hear. I'm looking forward to the things that will be learned as this capability is picked up by more shooters. We would all like to have a radar capable of tracking bullets deep into subsonic. This is the next best thing. I've used it side by side with long range radar and they gave the same result.
 
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Most here probably know but to the new users I would suggest when testing with the Infinition Radar or the Oehler 89 that all testing be done in a cross wind direction as close to full value as possible to get the really accurate reads for TOF data especially at the longer ranges . We tested the 89 today in 3-14 mph 6 o"clock tail winds today which I do not ever do normally for testing the vertical components of shots , but today I did not have a choice , The winds were steady and changing slowly enough to cherry pick the wind speed conditions to get some 1000 yard reads and get data as to the effects of the tail wind measurements at least. A Berger 407 measured with a 14 mph tail wind the BC 10 shot averages were .542 , in a 3-4 mph tail wind the BC averaged .517, close to zero tail wind averaged .507 , actual was .498 trued on AB with this particular rifle in a dead calm.

Tim in TX
Tim, The 89 does have the ability to correct for wind. If you put in the speed and direction of the wind it should provide you with a consistent BC number. You can experiment by replaying the data with and without wind input in the software and see if it closes down on your .498 number. If you constantly leave the wind values zeroed out then yes you can expect to get different numbers.
 
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Tim, The 89 does have the ability to correct for wind. If you put in the speed and direction of the wind it should provide you with a consistent BC number. You can experiment by replaying the data with and without wind input in the software and see if it closes down on your .498 number. If you constantly leave the wind values zeroed out then yes you can expect to get different numbers.
Thank you for that info , Buford had mentioned that as well. To be honest I do not think I could enter the down range wind data accurately especially at the apex of the trajectory when we were shooting at 2800 yards. In this particular terrain we were shooting over 1 mountain top and 2 valleys which made it particularly difficult to judge wind speeds and updrafts in a light headwind so for that reason I want to play with the numbers after I get data confirmation from everybody else that were testing at that time. I am absolutely looking forward to trying to match up the numbers. We will all be at the king of two miles match and I should be able to get some great data confirmation of our Oehler system results. I am taking the lap top with me to Raton,NM to compare our test results with the actual data from the match while also making sure I did my job right. It should be interesting.

Tim in TX
 
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Tim, The 89 does have the ability to correct for wind. If you put in the speed and direction of the wind it should provide you with a consistent BC number. You can experiment by replaying the data with and without wind input in the software and see if it closes down on your .498 number. If you constantly leave the wind values zeroed out then yes you can expect to get different numbers.
One of the best things about this system is the ability to shoot once and analyze variables later. Shoot the test once then change whatever variable you are interested in and replay the test.
 
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Tim, The 89 does have the ability to correct for wind. If you put in the speed and direction of the wind it should provide you with a consistent BC number. You can experiment by replaying the data with and without wind input in the software and see if it closes down on your .498 number. If you constantly leave the wind values zeroed out then yes you can expect to get different numbers.
Do you know how the system accounts for Wind? I cannot imagine how because the BC is derived from raw velocity measurements.
 
One of the best things about this system is the ability to shoot once and analyze variables later. Shoot the test once then change whatever variable you are interested in and replay the test.
I'm really interested in the 89. Can you link me to where I can get more info on how you change variables to adjust the results?
 
I'm really interested in the 89. Can you link me to where I can get more info on how you change variables to adjust the results?
The variables are in the settings. You input atmospherics, screen spacing and distance to target. After shooting you can change those variables and replay the test. I'll send you my email address in a PM.
 
I'm really interested in the 89. Can you link me to where I can get more info on how you change variables to adjust the results?

It's worth noting that you need a laptop to use the 89. You install their software where you input all the environmentals and distance measurements (target distance, distance between skyscreens, etc.) before shooting. You then save the tests then go back and re-run the saved shot strings with different environmentals to see how they affect the results. There's a lot way to use the data and software is pretty comprehensive.
 
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We have had some amazing results from the Oehler 89 this weekend so far , 2 of the 3 shooters I tested for a couple of weekends back are in the finals tomorrow at the king of two miles. All three doubted their Oehler results , they all thought their BC was higher than the Oehler reported .5109 on one gun and .5101 on the other. This was after the agreed upon wind speed was changed from 12 mph to 14 mph. it only changed the numbers slightly. They said it just could not be that low lol. They also claimed the expected and trued BC was .523 but in all fairness they only had difficult wind conditions to get that number. Well after we compared my data inputs, winds speed and directions and environmental's and went through the numbers last night, we ended up today confirming the truing up with the first shooter and the next two made it to the finals tomorrow . .510 was the perfect match for all of the 3 guns which happen to be identically built and have the same number of rounds through the barrels as well. The elevations matched surprisingly well so far and I hope they do well in the finals tomorrow. Big thumbs up for Buford and also Ken and Justin at Oehler.

Tim in TX
 
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We have had some amazing results from the Oehler 89 this weekend so far , 2 of the 3 shooters I tested for a couple of weekends back are in the finals tomorrow at the king of two miles. All three doubted their Oehler results , they all thought their BC was higher than the Oehler reported .5109 on one gun and .5101 on the other. This was after the agreed upon wind speed was changed from 12 mph to 14 mph. it only changed the numbers slightly. They said it just could not be that low lol. They also claimed the expected and trued BC was .523 but in all fairness they only had difficult wind conditions to get that number. Well after we compared my data inputs, winds speed and directions and environmental's and went through the numbers last night, we ended up today confirming the truing up with the first shooter and the next two made it to the finals tomorrow . .510 was the perfect match for all of the 3 guns which happen to be identically built and have the same number of rounds through the barrels as well. The elevations matched surprisingly well so far and I hope they do well in the finals tomorrow. Big thumbs up for Buford and also Ken and Justin at Oehler.

Tim in TX
That is great to hear, Tim. Thanks for the detailed explanation. I've long believed in the technology.

During the early testing, I once loaded a bunch of bullets backwards (to have as much drag as possible) and measured the BC at 500-without sighting rifle in, I just used holds. About a month later, I sighted the rifle in at 100 yards, used my Oehler Data to adjust for 500 and fired 5 shots on paper. The group center was about 1" low and 1/4" right of the "X". That bullet started at about 1.6 Mach and impacted at about .7 Mach.

My wife asked "Are you surprised?". I said "No, but I am relieved".

I look forward to learning more as you, and others like you, make use of this new capability.
 
I did some interesting testing on the effects on muzzle blast and seating depth effects on the bullet with the Oehler 89 and wanted to share some of my findings , although I am not through with the testing I was most excited about how the Oehler System 89 is shedding some light on my studies. I realize the Oehler is recommended at 300 yards and out, but I need data that is close to the muzzle out to 100yards ,and was my primary reason for purchasing this system. Justin at Oehler thought this system would show what I needed when I asked about this particular problem and he was absolutely right . As was stated by Dr. Oehler all data input has to be accurate for accurate results . It is so critical when it is that close. I strive to to achieve what Dr. Oehler stresses for the most correct data , environmentals are updated every 5 minutes and the exact distance was measured with a 300ft Tape measure to the inch and confirmed as well with a Sig 5000 . What I want to measure is the bullets slight instability at the muzzle and document the reasons for it , if I can then I can relate it to differing factors then correct the problem if it exist on that particular rifle. I first used a known bad seating depth that created random dispersion verses a known good seating depth with level velocities and 1 hole groups. The Oehler was able to measure the change in both BC and velocity drop down range to that indicates the bullets are in fact wobbling right out of the muzzle. Now this is still a relatively small shot sample to most considering the small change in measurements to read but the 120 shot sample from 3 sessions so far is showing measurable changes never the less , The changes noted so far : Average velocity drop from muzzle to target is 3 fps more with bad seating depth . Average BC drop is .006. Then the testing shifted to brake and suppressor effects and this is where it got interesting. I was able to measure the changes in BC and more importantly the BC standard deviations. I soon realized that the muzzle brake and suppressor blast pattern have a large effect on BC variation at least close to the muzzle. In the past i used to think that the bullet was solely responsible for this BC variation due to manufacturing differences but that is not always the case it appears. The suppressor with a change from cold pop or oxygen in the can show a higher BC variation then after the third shot levels out the BC variation to near perfect SD for 5 shots in a row with and without the bad seating depth. The oxygen seems to be effecting the first/second shot BC variations or it is the heat of the exit atmosphere and or the projectile . I am not sure yet but in a week or so I will purge the oxygen out of the can with inert gas to try and see if we can find the reason for the differences . I am waiting for the gas now and hopefully will have some really good documented data. This Oehler 89 is really paying for it self and I am so relieved it can measure this small stuff to a reasonable certainty providing I do my job right.


timintx
 
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I did some interesting testing on the effects on muzzle blast and seating depth effects on the bullet with the Oehler 89 and wanted to share some of my findings , although I am not through with the testing I was most excited about how the Oehler System 89 is shedding some light on my studies. I realize the Oehler is recommended at 300 yards and out, but I need data that is close to the muzzle out to 100yards ,and was my primary reason for purchasing this system. Justin at Oehler thought this system would show what I needed when I asked about this particular problem and he was absolutely right . As was stated by Dr. Oehler all data input has to be accurate for accurate results . It is so critical when it is that close. I strive to to achieve what Dr. Oehler stresses for the most correct data , environmentals are updated every 5 minutes and the exact distance was measured with a 300ft Tape measure to the inch and confirmed as well with a Sig 5000 . What I want to measure is the bullets slight instability at the muzzle and document the reasons for it , if I can then I can relate it to differing factors then correct the problem if it exist on that particular rifle. I first used a known bad seating depth that created random dispersion verses a known good seating depth with level velocities and 1 hole groups. The Oehler was able to measure the change in both BC and velocity drop down range to that indicates the bullets are in fact wobbling right out of the muzzle. Now this is still a relatively small shot sample to most considering the small change in measurements to read but the 120 shot sample from 3 sessions so far is showing measurable changes never the less , The changes noted so far : Average velocity drop from muzzle to target is 3 fps more with bad seating depth . Average BC drop is .006. Then the testing shifted to brake and suppressor effects and this is where it got interesting. I was able to measure the changes in BC and more importantly the BC standard deviations. I soon realized that the muzzle brake and suppressor blast pattern have a large effect on BC variation at least close to the muzzle. In the past i used to think that the bullet was solely responsible for this BC variation due to differences in manufacturing differences but that is not always the case it appears. The suppressor with a change from cold pop or oxygen in the can show a higher BC variation then after the third shot levels out the BC variation to near perfect SD for 5 shots in a row with and without the bad seating depth. The oxygen seems to be effecting the first/second shot BC variations or it is the heat of the exit atmosphere and or the projectile . I am not sure yet but in a week or so I will purge the oxygen out of the can with inert gas to try and see if we can find the reason for the differences . I am waiting for the gas now and hopefully will have some really good documented data. This Oehler 89 is really paying for it self and I am so relieved it can measure this small stuff to a reasonable certainty providing I do my job right.


timintx
Using an '89 to measure Launch Dynamics? Something I'd not thought about doing. It will be interesting to follow your results.

I've said it before, the '89 will provide some answers but using it will probably create more questions.

Thanks for sharing your test results.
 
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Using an '89 to measure Launch Dynamics? Something I'd not thought about doing. It will be interesting to follow your results.

I've said it before, the '89 will provide some answers but using it will probably create more questions.

Thanks for sharing your test results.
I agree Buford . I still need more shots in the samples but sometimes the result is heartbreaking and sometimes it is encouraging . I am looking forward to both . The guys at Crain said I could get quiet and stable with the right suppressor design but I have yet find the right combo to do so . I have a design that stabilizes the Bullets to a significant degree and with a super small flame signature but it is still fairly loud. So finding the right combo of my design with a baffle that reverses the flow of air is a tall order ,But I will stay at it and hope for the best . If it fails , I can at least fall back on my original design.

timintx
 
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I've recently heard from another purchaser of an '89 system. I know the first batch was sold out so looks like they are now shipping again.

There is lots to be learned from this technology and I encourage any users that might have questions to reach out to me if you have questions about setup or using it.
 
The latest update to the Hornady 4DOF program includes reporting time of flight to 5 decimal places.

If you have an '89 (or other way to measure time of flight), you can adjust the AFF in the program to make the prediction a best fit to your measured time of flight.

Time of flight is not influenced by AJ, a jerked trigger, a canted rifle, an incorrect zero, etc.
 
I thought it might be beneficial to start sharing some of the things we've learned using the 89 just in case anyone is browsing this thread and runs across the same issue.

One of the more common issues is test names. You should not use "." (periods) or "_" (underscores) in your test name. I personally use a format that includes cartridge, bullet weight, bullet kind, powder weight, powder kind. It looks like this for example: 300PRC 220 Berger LRHT 80p0 H1000. Note the p instead of .

Don't use wet plywood or OSB or any other wet material for your target board if using it in Impact mode.

If using the flyover array or square array make sure the microphone plane is not too close to your target, there needs to be some spacing to allow the Mach cone to reach the mics, but make sure that spacing is subtracted from your distance to target measurement input into the software. I typically put the mics 1 yard in front of whatever I'm shooting, laze the target, and subtract that 1 yard from the software input.

If anyone else has any tips or tricks please post them!
 
I thought it might be beneficial to start sharing some of the things we've learned using the 89 just in case anyone is browsing this thread and runs across the same issue.

One of the more common issues is test names. You should not use "." (periods) or "_" (underscores) in your test name. I personally use a format that includes cartridge, bullet weight, bullet kind, powder weight, powder kind. It looks like this for example: 300PRC 220 Berger LRHT 80p0 H1000. Note the p instead of .

Don't use wet plywood or OSB or any other wet material for your target board if using it in Impact mode.

If using the flyover array or square array make sure the microphone plane is not too close to your target, there needs to be some spacing to allow the Mach cone to reach the mics, but make sure that spacing is subtracted from your distance to target measurement input into the software. I typically put the mics 1 yard in front of whatever I'm shooting, laze the target, and subtract that 1 yard from the software input.

If anyone else has any tips or tricks please post them!
One I might add is make sure the sky screens are aligned with the Bullets flight path vertically for the most accurate velocities, when shooting on ground that is sloping it is tricky , I learned the hard way lol.
 
One I might add is make sure the sky screens are aligned with the Bullets flight path vertically for the most accurate velocities, when shooting on ground that is sloping it is tricky , I learned the hard way lol.

I 3d printed aiming devices that drop in where the screens go so all three are lined up perfectly. I can share the drawing if anyone wants it.
 
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I 3d printed aiming devices that drop in where the screens go so all three are lined up perfectly. I can share the drawing if anyone wants it.
Sure that would be great. I tend to get in a hurry sometimes which is usually not good .

Timintx