Chrono's don't agree... At all

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MACTEN

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I finally got around to doing some tuning with the new Pro-Chrono DLX (trying to replace the Caldwell since it no longer works with IOS updated and Caldwell doesn't care to update the app)
What I found was that all my shots with the Pro_Chrono are about 25 fps slower than the Caldwell records them.
I ended up putting them inline front to back and switched them several times.
All shots were at 12 feet from the chrono's.
Both were also used independently of either so as to take the light kits iterfearing with each other out of the equation.
I guess this means all my tuning I've done with the Caldwell is either right or wrong.
Everything else was about the same in regards to ES but what used to be 912 was 887 and this was repeated with 3 different airguns getting 25 fps difference.
Anyone have a similar finding? Maybe I need an FX pocket chrono.
 
well i did not expect these to be calibrated Measuring devices, like say the Mitutoyo equipment at work ASO

It is sort of the same with the GPS in all dashcams, no court will ever take the speed measurement of a 200 dollar camera to heart, which is also fine CUZ you can get the 100 % exact speed with the video alone + a little simple math.

Of course in your / our case here, well when yo say i shoot so and so pellet in this gun with this and that pressure, and at this speed, another person might not get the same result, but he should at least be in the ballpark.
Also just what i expect from the dials on some FX rifles, i do not expect to get the same result even if 2 similar rifles are set to the same parameters.

If you get a FX chrono, you probably just get a #3 number.

If you like the old chrono that "died" due to IOS support isues, well i would just get a cheap new / used android phone / tablet and just use that for the chrono, even if this of course mean yet another device to keep track off and keep charged.
 
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Ive said several times it's not like you really have anyway to calibrate one..

A guys pretty much at the mercy of what he gets. Got to wonder say you got 10 same cronies in a row how many are going to spot on or even +/- 2 ..lol.

25 fps is a good gap then like said how do you know what ones right ?

Maybe chance send it back on rma replacment and hope the next meets your satisfaction or gives you that 25 fps back ? Maybe be the next is 50 fps off from the first..

Or if you know people with one you can use there's and see what there's says ? ..
 
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Hateful McNasty said:
Ive said several times it's not like you really have anyway to calibrate one..

A guys pretty much at the mercy of what he gets. Got to wonder say you got 10 same cronies in a row how many are going to spot on or even +/- 2 ..lol.

25 fps is a good gap then like said how do you know what ones right ?

Maybe chance send it back on rma replacment and hope the next meets your satisfaction or gives you that 25 fps back ? Maybe be the next is 50 fps off from the first..

Or if you know people with one you can use there's and see what there's says ? ..
Click to expand...
It's still in the return window so that's not a bad idea! :) But .. yeah what if the new one is 50 fps off the other direction.. hmph lol
 
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allan_wind said:
FX Chronograph does not have any specification for accuracy just so you know. Competition Electronics does specify the accuracy of their devices including the ProChrono DLX. They also have excellent support so I would call them or drop them an email and see what they say. strlok+ has a trajectory validation feature.
Click to expand...
I called them when It happened and they had nothing to offer for advice.
 
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Come on guys, it's not like these little toys are life saving equipment !!
There is NO...world wide, or even USA wide calibration standard that...ALL...manufacturers use. All of these companies build to their own designs and a very...generalized standard.
There IS NO, watchdog standard that keeps track of ANY of the companies that make chronographs.
Otherwise...these tools would cost three or four times MORE money.

Many of the chronograph companies state somewhere between 97% and 99% accuracy.
BY WHO"S STANDARD ? ThereISN'T one !

I did some searching for any ACTUAL test standard that these things are built to before I bought mine. I brought it down to two brands. Did more searching. Before buying, I e-mailed the two companies with a few questions about both "accuracy" and "repeatability". Both companies commented on my "repeatability" question, but just did some general ramblings about the "accuracy" part, that really had no base in reality.
I asked both companies for more informative information. If this would have been a phone call, it would have amounted to a hang up, by both companies !!!

I KNOW how things go when you ask too deep or informative questions on how things work, or how they measure. Remember, I worked in the Aerospace Industry since the mid 80's, and specifically in the "test" part of the industry for the last 12 or so years before I retired.

I remember getting bumrushed out of a sales area of the SEMA Show (big Hot Rod/Race Car, parts show), when I tried to get accurate information about the material the company used for their anti-sway bars that they made (car suspension parts) ! Companies don't like being called out on their parts !

All this is to say, use what you have. As long as the chronograph you own is fairly repeatable...use it, and that one ONLY to test YOUR equipment. If you have two...pick ONE.

Mike
 
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JEFFPPC said:
Does it matter. To me the point of the chrono is to give me a reference to tune rifle to pellet. As long as it is repeatable I don't care if it's absolute or not. Using multiple chronos is a rabbit hole similar to the one borescopes have created. I do not rely on programs to give me drop figures, I shoot them.
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It matters of course. I like to tune to known velocities that work, prior to hitting the range.. 25 fps is a huge difference.
 
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ProChrono DLX specification says "accuracy +/-.5% of measured velocity or better". With my Taipan Veteran w/ ProChorno DLX I was getting 258 m/s and extreme spread of 4 m/s over 7 shots (I was making power adjustments in a series of 75 shots). When I looked the only thing more accurate was Lab Radar but it was cost prohibitive for me. Don't overlook the trajectory validation point I made earlier. Tool is a tool and it has to work otherwise it's useless to me.
 
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I have had 3 chronos, Caldwell, ProChrony, Shooting Chrono, plus two Radar Chronos, the FX radar Chrono and a new Labradar.
I haven’t used the LABRADAR yet, but I have tested the others against each other over many years. I tested the three optical chronos many years ago and got about a 2.5% difference between them. I tested the ProChrono against the FX Radar Chrono. About a 2.5% difference. And it varied as to which one was faster. They each weren’t consistently faster or slower.

However, they were ALL internally consistent. In other words, the Caldwell was consistent, the ProChrony was consistent and the old Shooting Chrono was consistent. In addition my FX radar chronograph is consistent.

They’re just not consistent with one another.

When i tune I do o based on consistently, plus consistency of change when I make changes to the gun. As long as i use only ONE Chrono I am fine when I get the consistency I want (small ES and SD) coupled with excellent accuracy.

Why would I care if the numbers are all writhing 2.5% of each other?
 
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If you always use your crony what difference does the number make. I know what pellet shoots in my Airgun at a given coped from my Lab Radar. I have used different springs in my TX200. One that gives 807 likes AA 8.44. It does not like AA 10.33 near as well. If I put the spring in that gives me 896 it now prefers the 10.33. Now, am I getting the correct speeds? For my used it does not matter. If I respring and its 817 I know the first pellet I will try is the 8.44. Well, I did this and its evidently still in the node. Now if the sppeds I am reading are actually 50 fps fast, does not matter. I used my known speeds and info to select the pellet that worked irregardless of the chrony error.
 
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MACTEN said:
I finally got around to doing some tuning with the new Pro-Chrono DLX (trying to replace the Caldwell since it no longer works with IOS updated and Caldwell doesn't care to update the app)
What I found was that all my shots with the Pro_Chrono are about 25 fps slower than the Caldwell records them.
I ended up putting them inline front to back and switched them several times.
All shots were at 12 feet from the chrono's.
Both were also used independently of either so as to take the light kits iterfearing with each other out of the equation.
I guess this means all my tuning I've done with the Caldwell is either right or wrong.
Everything else was about the same in regards to ES but what used to be 912 was 887 and this was repeated with 3 different airguns getting 25 fps difference.
Anyone have a similar finding? Maybe I need an FX pocket chrono.
Click to expand...

I agree with jeffppc. To me, your target will tell you what you need to know. Ultimately it's about accuracy. A chrono doesn't tell you what your groups are, that information is on paper. Going from 25yds to 50yds to 75yds to 100yds shows the trajectory (path). Too loopy, more power is needed. If reg, hammer and t-port are maxed then lighter projectile is needed. Again, the goal is max speed that shoots tight. The chrono absolutely saves us time and a lot of traipsing back and forth to our targets. But in the final analysis, an accurate chrono is not essential for tuning. Imo.
Bill and Addi
 
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