Weird Chronograph Numbers

Status
Not open for further replies.

nevadabob

Member
Joined
Feb 1, 2012
Messages
512
Location
Reno NV
Went out shooting about 9:30 this morning testing some new 9mm loads with 2 different semi's. It was somewhat windy & partly cloudy. Out of 15 shots with one pistol, I got 3 that read "189, 192, 179" with the rest being around 1064. With the second pistol, I got 3 readings that were similar to the above and the rest in the 1050-1060 range.
I called Pro Chrono but the tech was not available. Both guns behaved well. With the low numbers, there was no difference in recoil, brass ejection, slide action, accuracy, etc. I'm assuming these were "environmental glitches" and nothing to worry about. Anyone ever come across this before?
 
Yeah, the first time I went out with my Master Chrony, the first couple of shots out of my 9mm registered 1600 and change! I'm pretty good at reloading, not THAT good. Moved the chronograph out another 5 feet, seemed ok. The next time, set it up the same way as I did the first time, 5 yards, perfect all day, IDK, might have been the sun angle the first time.
 
Muzzle was 10' in front of. I did have the diffusers up, maybe that contributed somewhat.
 
I also try to do my Chrono work around 11:00- 3:00. Try drawing a black ring around the bullet with a sharpie.
 
Same here. First few hours and last few hours of the day are pretty much a waste with a chrono. Like Gahunter I try to use the middle 4-6 hours of the day when the sun is more or less overhead. Early or late times do yield erratic results.
 
One trick that I learned recently is that you can rotate the entire Chrony unit to aim the skyscreens directly at the sun, even when the sun is low on the horizon. Take the screens to the sun, so to speak. The Chrony works great arranged this way.
 
Chrony reading can get all messed up if your too close to the chrony. Apparently, and something I've pretty much confirmed, is when I get these weird readings, the unit is trying to read sound waves/muzzle blast, rather than the physical projectile passing over. When I back off another 10'-ish my chrony will produce very normal numbers.

I think that's how I understand things as explained by the manufacturer.

GS
 
No trees, no shade, out at a makeshift BLM desert shooting spot. Since it was partly cloudy, I'm now thinking the "covered" sun with the diffusers on could've been the culprit. And I'll increase the muzzle to chrono distance to 11 feet.
 
Chrony reading can get all messed up if your too close to the chrony. Apparently, and something I've pretty much confirmed, is when I get these weird readings, the unit is trying to read sound waves/muzzle blast, rather than the physical projectile passing over. When I back off another 10'-ish my chrony will produce very normal numbers.

I think that's how I understand things as explained by the manufacturer.

GS
The first time I used the Master Chrony, (remote screen, this is my THIRD chronograph, my son shot the first, I got the second), with the expensive part out of the way, I can put a steel plate on the front of the Chrony. When I had to move it further away, I could no longer keep the remote on the table where I was shooting from, had to put it on the ground, not too big a problem, just a bit irritating. The second time, all was perfect.
 
I've found that sometimes my chrono works best when both sensors are in the shade.
Sometimes that means using a piece of cardboard to cover the entire top of the sky screens.
 
Make sure Chrono is in good light or what I call "even light", overhead not sideways light like at sunrise or sunset. In the shade is fine as long as there's open skies above it. If it's cloudy, don't use the diffusers, you don't need them unless it's sunny.

Make sure it's level too, I set mine up on a tripod and make sure everything is level before I shoot through it, and make sure the metal rods are straight, not bent because a bent rod will throw velocities WAY off, and make sure the battery isn't weak because a weak battery can give bad numbers. And of course stand at least 10ft away and shoot through the leveled Chrono level-ey.

I also like to run just a few test loads through it first, loads that I know what velocity they're supposed to be going. If something is off with those, there's no point chronographing the other rounds until it's fixed.
 
About 4 paces from the muzzle should be far enough to get a good reading - much further, & you increase your odds of shooting the chrony. Clouds should not bother it. My Pro Chrono has worked fine in all kinds of light.
 
Vol, likewise for me, my other Chronograph was a Chrony, and it was a great little gadget until it just got old, my next one is the Pro Chrono and so far I haven't had a problem with it, hand guns I set it up about 2 yards from the muzzle, and rifle I set it up 3 yards from the muzzle.
 
glad I bought a Pact Pro , the only bad reading I ever got was from weak batteries , so when I read the OP's post, that was the only thing that came to mind , check the batteries ,
 
I had some minor problems getting my chrony up and running, too. My first seven shots wouldn't register at all. I wondered why all the guys on the other benches were snickering and then I realized I had it set up backward.

The only real trouble I've had is with side lighting reflecting off the bullet and giving me high readings. The instruction manual suggests darkening the bullet with a marker, but I decided to make some home-made shades to block the sun instead. I went to staples and bought some black posterboard (the kind with sandwiched foam) and cut a piece to fit each side. Works like a charm.
 
Sorry to say but the Chrony Brad just doesn't like SUN. I tried 2 of them and returned them. Tried extra shading, sky screens whatever.

Never could get constant readings, nothing but errors.I can't post how I really feel about them!;)

I bought a Competition Electronics and never had an error with it. On sale for around $100.

There are several long threads here on it.

Save yourself heartache and despair:D



http://www.midwayusa.com/product/852429/competition-electronics-prochrono-digital-chronograph
 
I have the same unit. It is not a high end chronograph and I've just learned to expect nonsensical numbers at times. In the 4-5 years I've owned mine I've had 3 range visits when I got numbers that made no sense at all and nothing I tried seemed to help. The next time out all was good. Any chronograph is more accurate in subdued light.

For no more than I paid, I can live with it once in a while. From the reports I've read they tend to be accurate within 1% of chronographs costing far more, but can at times be a bit picky about working. If I truly needed a better unit, I'd buy one.
 
I've found that my results are far nor consistent and repeatable when I use a dark sharpie on the entire bullet.

It works out well because I can color code bullets when shooting ladders and the ink will mark the Target so I know which load made a particular hole.
 
I always get a kick out of those who accidentally shoot their chrony's. I even chrony at shooting distances out to 200 yds, been lucky I guess, cause I haven't shot one yet. And now that I've said that, and don't have a piece of wood to knock on, I'll probably blow mine to pieces tomorrow. My biggest problem has been knocking them over with muzzle blast. But I've solved that problem by weigh my tripod down with a bag of lead shot. But still, getting too close will mess the reading up.

GS
 
...or we could check out www.mylabradar.com, plunk down $500, and have all the digital problems solved!

No, you would have to get a Dillon.:rolleyes: Oh they don't have one so spend $100 and get the Competition Electronics and life is good, No sharpies on your bullets or shooting at certain hours of the day or Phases of the Moon and Sun.
 
Status
Not open for further replies.
Back
Top