Old vs New Chronograph Technology

[Richard22]

So how does the accuracy of the new Doppler-based chronographs truly compare with that of the earlier models that use a much more simple approach? How would anyone know which models are truly the most accurate when you consider the lack of independent testing against a known standard? Are we to continue on the current path where accuracy is assumed in relation to price using numbers quoted by the manufacturer?

 

[Richard22]

Follow up...

Went to the range this morning to get some data to send to Leupold for my new CDS turret and ran into a guy who asked to compare readings between by relatively inexpensive Caldwell model and his $600 Garmin. Less than a 10 fps difference in three readings between the two.

 

[Carl]

These are the chronographs I trust enough to use velocity data instead of shooting drops at range and back calculating:

Garmin
Magnetospeed
Labradar
Well set up Ohler

Some of the other new radar based ones may be trustworthy but I’ll hold off until I see plenty of data come in.

Other chrono’s MAY give accurate results, but I wouldn’t trust them, certainly not the cheap sky screen models.

 

[RealMuddyboots]

These are the chronographs I trust enough to use velocity data instead of shooting drops at range and back calculating:

Garmin
Magnetospeed
Labradar
Well set up Ohler

Some of the other new radar based ones may be trustworthy but I’ll hold off until I see plenty of data come in.

Other chrono’s MAY give accurate results, but I wouldn’t trust them, certainly not the cheap sky screen models.

Trustworthy? All chronographs have at least 0.1% accuracy deviation. So which one is truly the closest the true velocity? No chronograph is absolutely accurate to a bullets actual velocity. They all have different means of detection, sensors are not all the same, all have different means of calculating velocity from their sensors. The only thing we have to go on is whether a chronograph provides consistent results to itself. Optical chronographs are quite accurate to other chronograph results if they are correctly set up each and every time they are used.

I recently bought an Athlon Rangecraft that seems to be pretty consistent to itself which is all I ask of it.

There isn't a chronograph that I would trust without verifying drops.

 

[RealMuddyboots]

FYI,
Garmin - Athlon - Labradar
As examples

 

[Potsie]

Trustworthy? All chronographs have at least 0.1% accuracy deviation. So which one is truly the closest the true velocity? No chronograph is absolutely accurate to a bullets actual velocity. They all have different means of detection, sensors are not all the same, all have different means of calculating velocity from their sensors. The only thing we have to go on is whether a chronograph provides consistent results to itself. Optical chronographs are quite accurate to other chronograph results if they are correctly set up each and every time they are used.

I recently bought an Athlon Rangecraft that seems to be pretty consistent to itself which is all I ask of it.

There isn't a chronograph that I would trust without verifying drops.

So let’s think about this for a second - my Garmin tells me my 6.5 load is clocking an average of 3250 fps. So the given velocity is +\- 3.25 fps from the actual velocity? Thats about 33% of a single digit SD. Talk about picking the pepper from the fly chit.

My Garmin has yet to drop a shot 1.5 years of use, and I shoot quite a bit.

Can’t say that about any of the three previous chronographs I’ve used. So to get back to the OP’s question, infinitely more accurate, because that accuracy number also included all the shots that don’t read.

 

[mtmuley]

Shoot paper. mtmuley

 

[RealMuddyboots]

So let’s think about this for a second - my Garmin tells me my 6.5 load is clocking an average of 3250 fps. So the given velocity is +\- 3.25 fps from the actual velocity? Thats about 33% of a single digit SD. Talk about picking the pepper from the fly chit.

My Garmin has yet to drop a shot 1.5 years of use, and I shoot quite a bit.

Can’t say that about any of the three previous chronographs I’ve used. So to get back to the OP’s question, infinitely more accurate, because that accuracy number also included all the shots that don’t read.

So talking about stepping in fly chit! My humblest apologies for my dumas math error!



So far, my new Athlon has not dropped a shot in about 300+ rounds so far, so it appears to be on right path as well.

 

[brockel]

These are the chronographs I trust enough to use velocity data instead of Other chrono’s MAY give accurate results, but I wouldn’t trust them, certainly not the cheap sky screen models.

I’ve seen some wild numbers come out of the cheaper sky screen models.

 

[RealMuddyboots]

So talking about stepping in fly chit! My humblest apologies for my dumas math error!



So far, my new Athlon has not dropped a shot in about 300+ rounds so far, so it appears to be on right path as well.

Wow, gotta apologize for last night posts. I was celebrating a very difficult but successful surgery on a friend of mine. Should not have been posting anything anywhere. "Liquid interference." My chronograph post is WTH!

The good news is my "brother from different mother" is going to be fine.

 

[Richard22]

Because velocities change so quickly after a bullet leaves the muzzle, I have to wonder how the newer technologies are able to compensate for the time needed to calculate a reading relative to the distance traveled. In other words, while they may be more accurate in determining a velocity, what about the accuracy in determining the true, instantaneous muzzle velocity? Surely some form of "fudge factor" is not at play here to compensate for the distance a bullet must travel from the muzzle before it's picked up by the chronograph, as well as the distance it must travel to determine its velocity.