Detailed Comparison of the LabRadar, MagnetoSpeed, and Two-Box chronographs

[Ammolytics]

Hey everyone!

Wow, this one was a lot of work but it's finally here! If you've ever wondered how these chronographs stack up to one another, or want to drown yourself in data this weekend, then I've got an article for you.

https://blog.ammolytics.com/2019-09-06/chrono-comparison.html

For this test, I fired a 25 rounds through a suppressed bolt action and 50 rounds through a semi-auto National Match service rifle. Going in, I didn't think it was going to be enough. Now I know that I was probably in over my head. Writing a detailed review for one device is hard enough, but here I did THREE.

It's a long one and there's a lot to process, but there's also plenty I left out to avoid overwhelming readers. I'd love to hear your feedback and answer any questions!

 

[RegionRat]

A couple of comments.

When I have lost power on the LabRadar, it doesn't loose the memory. Darn shame that battery gave out before you could finish.

Darn shame that transducer on the Two Box Chrono was off. Knowing Adam, I doubt that behavior was normal. I would also ask him about how the data transfer is supposed to run.

It was a lot of work and maybe those issues could be addressed and some of it could be repeated to get to the bottom of things.

 

[Ammolytics]

A couple of comments.

When I have lost power on the LabRadar, it doesn't loose the memory. Darn shame that battery gave out before you could finish.

Darn shame that transducer on the Two Box Chrono was off. Knowing Adam, I doubt that behavior was normal. I would also ask him about how the data transfer is supposed to run.

It was a lot of work and maybe those issues could be addressed and some of it could be repeated to get to the bottom of things.

Yeah, the memory persists on the LabRadar if power is lost -- that's one benefit of the SD card. The only data I lost were rounds not recorded from 1) inadequate sensitivity when firing suppressed and 2) a dead battery which didn't allow me to continue using it.

Regarding the Two-Box Chrono: I did send a draft of this article to him and he did read it, though nothing in his brief response related to the tilted sensor. As far as the manual data transfer, that's just how it was designed. Maybe the simple approach is better for some folks.

Thanks for the feedback and taking the time to read my work, I appreciate it!

 

[David Christian]

Good job Eric!

 

[PatMiles]

As is well known, stand alone battery packs abound on Amazon. This was my first purchase after buying a LabRadar so I didn't have to worry about the onboard batteries going tango uniform at the wrong time. Highly recommended!

 

[dmoran]

Eric,
Great test ..... awesome logistics and reporting.
Very excellently done !.!.!

 

[Ballisticboy]

It is a pity that there is no picture showing the position of the LabRadar relative to the gun as it is critical to maximising the data available for the accurate working of the radar system. As well as pointing in the right direction the radar needs to be as close as possible to the muzzle of the gun. I would also worry about the position of the concrete structure shown in one of the pictures in front of the radar and its effect on the amount of data the radar is collecting. The radar will probably still give a muzzle velocity value with reduced data but the level of certainty for the answer will be much reduced due to the poorer curve fit possible for the smaller amount of data. The curve fit is needed to produce the muzzle velocity.
Good idea though to carry out the work and produce the results.

 

[Ammolytics]

Good job Eric!

Thanks, David!

 

[Ammolytics]

As is well known, stand alone battery packs abound on Amazon. This was my first purchase after buying a LabRadar so I didn't have to worry about the onboard batteries going tango uniform at the wrong time. Highly recommended!

The battery pack I used was loaned to me with the LabRadar. I believe it may actually be the same one that LabRadar sells. As I wrote, I'd really like to see the manufacture provide some guidance on the power consumption/requirements so that a proper battery can be paired with it for the use-case.

 

[Ammolytics]

It is a pity that there is no picture showing the position of the LabRadar relative to the gun as it is critical to maximising the data available for the accurate working of the radar system. As well as pointing in the right direction the radar needs to be as close as possible to the muzzle of the gun. I would also worry about the position of the concrete structure shown in one of the pictures in front of the radar and its effect on the amount of data the radar is collecting. The radar will probably still give a muzzle velocity value with reduced data but the level of certainty for the answer will be much reduced due to the poorer curve fit possible for the smaller amount of data. The curve fit is needed to produce the muzzle velocity.
Good idea though to carry out the work and produce the results.

You're right, I forgot to include a photo of the full setup! Thanks for pointing that out -- I'll add one.
It's possible that those concrete baffles have a negative effect, but I can't be sure. These types of things aren't well-documented by LabRadar.

RE curve fit: I did try a 2nd degree polynomial curve and it didn't fit their muzzle velocity as well. That said, the distances recorded by the trajectory files appear to change with the velocity distance settings. I was focused on shorter distances, and that's what I got. If the trajectory data had longer distances, then a linear fit may not work quite as well. This is all speculative though -- I'd need to see the data and run the analysis. The point is, LabRadar could do a much better job of just documenting how it works and what it can/can't do.

 

[hpshooter]

Thanks for the report!

 

[Turbulent Turtle]

Great job on the report.

I have a few nits to pick.
1- The 10-ring of the MR-1 target is 12 inches, not 10.
2- If your smartphone has a USB plug, you should get a USB card reader and that way you could read the SD card directly to your smartphone. These devices are fast and very cheap. My USB-C card reader is $12 on Amazon, from Cable Matters.
3- USB batteries are virtually a dime-a-dozen. The one provided by Labradar is a 10,000 mAh model. You can easily get larger capacity than that one, especially if you do get a Labradar; it seems to need a lot of power.

Again, good job on the report. It was clear and easy to follow.

 

[Ammolytics]

Great job on the report.

I have a few nits to pick.
1- The 10-ring of the MR-1 target is 12 inches, not 10.
2- If your smartphone has a USB plug, you should get a USB card reader and that way you could read the SD card directly to your smartphone. These devices are fast and very cheap. My USB-C card reader is $12 on Amazon, from Cable Matters.
3- USB batteries are virtually a dime-a-dozen. The one provided by Labradar is a 10,000 mAh model. You can easily get larger capacity than that one, especially if you do get a Labradar; it seems to need a lot of power.

Again, good job on the report. It was clear and easy to follow.

Thanks for catching my mistake on the MR-1 10-ring size, I'll correct that!

The phone/connection issue was with MagnetoSpeed's XFR, which connects directly to the head unit and relies on the headphone jack. I believe you have to use that if you wish to use their mobile app and it's even more important for folks with the Sporter model, which lacks an SD card. It's true that you can get an SD card reader for mobile phones though!

I relied on the battery pack which was provided by the person who loaned me their LabRadar. I certainly could have used a bigger batter pack and you're right, they are inexpensive. It would still really help to get documentation from the folks at LabRadar about power consumption so that we have a better idea of what to expect and can make educated decisions.

Thanks for taking the time to read my work and share your feedback, I really appreciate it!

 

[Ballisticboy]

RE curve fit: I did try a 2nd degree polynomial curve and it didn't fit their muzzle velocity as well. That said, the distances recorded by the trajectory files appear to change with the velocity distance settings. I was focused on shorter distances, and that's what I got. If the trajectory data had longer distances, then a linear fit may not work quite as well. This is all speculative though -- I'd need to see the data and run the analysis. The point is, LabRadar could do a much better job of just documenting how it works and what it can/can't do.

I was using much more powerful radars and the best fit I found in most cases was a fourth order polynomial but it does require an adequate number of points. I have been supplied with LabRadar data in the past and I was never absolutely convinced it was raw data as it did not look like all the raw data I have seen from other radars, in particular when the radar first detects the bullet. Only time and velocity can be considered as raw data on this type of fixed head radar. We were always using radars as pairs which had to agree to less than 1m/s. The radars would often start agreeing and then the gap in the MV readings would drift apart for no apparent reason. Both sets had been carefully set up but one set would have dozens of data points and the other four or five. Minute adjustments would usually bring back the required performance. The type of curve fit with an adequate number of data points should not make a great difference to the MV value if the radar is picking up the bullet soon enough. It will make a large difference to the drag curve if the data is being used to calculate Cd values, a straight line then not being adequate for the purpose.

 

[Pres100]

Enjoyed the article and was curious about the same comparisons, but would have loved to see a traditional optical chronograph mixed in as well - it had been the standard for the past 30-40 years.
There’s no doubt that the newer technology is making things easier and providing more useful data. I think that the lab radar style will eventually mature into the standard. My guess is that future versions of this will (or should) be far superior. It just needs to be as simple to use as the magnetospeed.
the potential for far more sophisticated and comprehensive data beyond the muzzle will prove a game changer.

 

[hogpatrol]

Good report and interesting reading. Thanks for taking the time to compile it and publish your results. Interesting observations on the effect of the Magnetospeed on accuracy.

 

[expiper]

the battery consumption rate is the first thing I noticed with my lab radar,,,,I got a battery pak (a big one,hahaha??) and now I can use it all day and only use ~ 1/4 of its juice,,,,Roger

 

[Twitch]

Nice write up. I have the labradar. I would be suspect of your battery pack. I use a cheap 10,000mah battery pack on mine all the time and have no problems with having the unit on (ON not ARMED the whole time) for hours and it killing the pack. It rarely used half. Now the battery pack only has a 4 led system for capacity so I'm going by lights left lit. As I just used it yesterday and had the unit powered on, not armed, for at least 3 hours and it only used 1/4 of the battery pack.
I just started using the app and I do have issues with it disconnecting when left sitting, but always connected back easily. Not certain what caused it because I would leave my phone next to the unit as I went in my house to load up more rounds. I have a large SD card that has well over 100 shot strings stored and it only takes a couple minutes to transfer all that data when connecting my phone to the unit. They are mostly 5 shot strings but I know there are quite a few 10-20 shots strings included.
The aiming of the unit was a challenge when I first got it. Now I keep a speed square in the bag with it. I hold it up just under the notch in the unit and works great. At my home range (100yds) I shoot down an old road bed. Its only 20' wide, with trees on both sides. Don't worry it's perfectly safe for shooting. I do loose the data at 75-100yds often. The few times I've used it in an open field/range it has done fine with getting the data at those distances.
I have yet to shoot anything suppressed or had a reason to Chrono my bow speed so can't give any insight on that. I have had some problems with it getting data on boat tail 22 caliber bullets out of a 22-250 but think that was more of a setup/aiming/settings issue because I've gotten consistent data for .223.
As with anything I've found associated with reloading, your mileage may vary. This is not to defend the labradar, just giving what I've found to be problems with it. This is only my second chronograph. My first was a prochrono. I hated the setup to use it. It's in a cabinet somewhere in my basement. I would really like to try a V3 for myself. Just to see what POI shift it makes or variations in my group size. Adams system looks to have potential and I will enjoy the readings to come as more people get experience with it. I think if my labradar went down today, I would buy the V3 just to try it out but would have no problem with buying another labradar. I purchased my labradar in Sept of '17.

 

[JimSC]

interesting article and thanks for taking the time to review. I use a Pro Chrono with bluetooth and am very happy with it. It takes a couple of minutes for the initial set up but once in position it works great and picks up 99.9% of my shots. I can take my muzzle velocity at 100 and the computed drop at 800 is within a half MOA on vertical. The software is excellent, connects flawlessly on all my electronic devices and gives me all the info I need for load development and record keeping. Batteries last forever it seems. If it died today I would happily drop 130 bucks for a new one. I tried a Labradar last year but it had too many quirks and not enough customer service so I sent it back to Brownells for a refund. If and when the Labradar version 2.0 comes out I may try it again, but the current version has too many problems and not enough advantages to make it worth my while.

BTW the opticals are very easy to setup using a laser boresighter and a small piece of cardboard, takes me less than 5 minutes

 

[Ammolytics]

I was using much more powerful radars and the best fit I found in most cases was a fourth order polynomial but it does require an adequate number of points. I have been supplied with LabRadar data in the past and I was never absolutely convinced it was raw data as it did not look like all the raw data I have seen from other radars, in particular when the radar first detects the bullet. Only time and velocity can be considered as raw data on this type of fixed head radar. We were always using radars as pairs which had to agree to less than 1m/s. The radars would often start agreeing and then the gap in the MV readings would drift apart for no apparent reason. Both sets had been carefully set up but one set would have dozens of data points and the other four or five. Minute adjustments would usually bring back the required performance. The type of curve fit with an adequate number of data points should not make a great difference to the MV value if the radar is picking up the bullet soon enough. It will make a large difference to the drag curve if the data is being used to calculate Cd values, a straight line then not being adequate for the purpose.

Wow, there is a ton of great info in here -- thank you for sharing!
I'd love to hear more about your experience. Feel free to shoot me an email if you'd like to share some stories, I'm all ears!