First of all I know this horse has been beat to death, I currently have a shootin chrony F1 that has been pretty reliable lately I have been questioning the velocities. I have been contemplating buying a different chronograph so I can compare the two, I would love an oehler but cannot swing the price without getting divorced. What would you recommend as a resonably priced alternative.

If you have any buddies with chronographs, shoot your loads over theirs and see how they compare.

I believe shooting chrony's rate their accuracy at 99.5%

ProChrono Digital. My Chrony F1 was replaced by a PCD, and I couldn't be happier.

Shooting Chrony advertises 99.5% accuracy ...@2000 fps. So they're admitting to a 10 fps random error. That extrapolates to 15 fps @3000 fps, 20 fps @4000. Good luck with your goal of an SD of 20 on your .204 loads when the chrono is randomly introducing a 20 fps error into your data.

A few years ago, the German defense laboratories tested the CED Millennium and found it 0.3% more accurate than the Oehler 35P. Since then, CED has replaced the Millennium model with the M2, which has a 12x faster processor than the Millennium did (and has at least 3x the precision of the model it replaced). They're $200, and if you add the optional infrared lighting, which makes them all but completely immune to unusual lighting conditions, they're still only 1/2 the price of an Oehler.

IMHO, the Competition Electronics Pro Chrono Digital is a better option than ANY Shooting Chrony (25% faster/more precise timing circuitry) and they're only $120.


Remember that comparing two chronos still only tells you how they differ. It DOES NOT tell you which is the more accurate.

An Oehler will outlast most marriages. My old M33 outlasted my first marriage. We'll see about my 35P and my second marriage.

Alan

PCD!!

A good check is still to shoot some .22LR and see how the reading compares to the advertised speed.

Second proof screen is very nerve-settling, and only one has it, Oehler. So glad they're offering 'em again

Divorce can be avoided using several techniques:

1) "That ol' thing?" Employ this sparingly, you're trying to convince her she's forgotten - not crazy.

2) "We talked about this!" Again, simply forgotten, not coo-koo.

3) "I traded a _____ to get it." Can be used in conjunction with #1, which is nearly a perfect strategy. Trading an imaginary item, that she must have forgotten about - devastating!

4)"Look what I won at a raffle!" Requires prior planning, and best sprung while there's a group -- family dinner or such -- to oughh and ahhhh over your fortunes.

Yes Sir.

A variation I use is to shoot loads that have a long history, first. You'd be amazed at the variences that things like natural light, or a few inches placement makes.

A little more pricy but I bought a Magnetospeed and I couldn't be happier. I have probably spent close to 1k for chrony's over the years. I love that it attaches directly to the barrel and uses the mass signature of the bullet. No more trips downrange to make sure the screens are set up inline. There will never be a lighting issue and you will get true muzzle velocity. I was skeptical until I began to use it, now I highly recommend it.

Here is a comparison done between the Oehler 35P and the Magnetospeed.

http://www.realguns.com/articles/391.htm

Glad they recognize who to try 'n' topple.

Might be dynamite for velocity, but no way to argue it wouldn't effect grouping. Not for me.

Thanks for all the insight and ideas, most of my buddies have the shooting chrony and the comparisons have been all over the place. I really am trying to find consistency I understand lighting has alot of impact in readings. Last weekend I chronoed a new 7mag between 11am and 1pm it was a little cloudy, three separate 10 shot strings from the same rifle same load exact same setup with chrony gave three different averages 2895 ,3025, 3056 all with screens. I let the barrel cool 3 minutes between shots 45 degrees out with a 10 mph wind

I have a prochrono digital and a shooting chrony F1. I set them both up and shot two different rifles over them working up loads with increasing powder charges. the F1 consistantly read ~50 fps faster than the prochrono. Cloudy day, no screens.

At least they were consistant. Have no idea which is more accurate.

I remember when Ken Oehler addressed the subject of comparing chronogrpahs, and made quite clear that the real test is to compare like-chrongraphs (Oehler vs Oehler, or ProChrony vs ProChrony). You're looking for consistancy, not perfection based on something subjective.

You could have ten different chronies all lined up, and fire the same load from the same firearm and prove nothing more than there's variance in machines. Line up ten of the same chronies, and shoot, there had better be agreement.

On that basis, it's Oehler - hands down.

Dont know about where you live, but I do know around here the sun moves a little more west each hour. Also the clouds do tend to change position also. This can cause diffrences in lighting on your chrony, hence a diffrence in speed readings. Also using (Sun) screens on a cloudy day isnt the best practice for consistent readings. Had a chance this weekend to compare a PCD with my beta master chrony as a guy had one at the range at that time readings were the same as far as I was concerned, maybe 20 FPS. Not going to trade one POS for another. I never look at speed until I get 5 shot groups like these. To me chronys are just another toy to play with, knowing velocity is fine, but if it dont group then it dont mean Chit.

Right is a 223 52gr going a whopping 3075, left is a Swift 52gr going 3650. Think the loads are consistent.



Or should I chrony this 25.06 load, or just go hunting with it.



Oh, but if my chrony happens to die (either a natural death, or by getting shot) then I will buy an Oehler.

Swifty

I use 2 chronographs....at the same time! Like you, I have a Chrony F1 sitting dead-center inside the 4' bar holding my Oehler 33 skyscreens. So, each time I fire a shot, I get a reading from both units.

FWIW, the Chrony is just as accurate as the Oehler, although it is not as user-friendly and lacks the bells and whistles that I kinda like (ie...statistical analysis).

One of my pet ideas (that I, out of my ignorance. keep promoting) is some sort of a "chamber" that provides (probably artificial) consistent lighting that is immune to sun position, clouds, passing butterflies, and other things that play hob with getting a consistent reading.

With the Shooting Chrony, if you leave the skyscreens in place, and a cloud comes over, your readings will drop. I always do my measurements on days when the clouds are thin enough that I can see the shadow of my tripod. I get very consistent results.

5sdad, I have a cute little mod figured out for my Shooting Chrony to do pretty much what you describe. Basically, you mount high intensity LEDs just behind the two photocells and replace the skyscreens with retroreflective tape, i.e. bounce light back toward the source. The photocells will be close enough to the LEDs that quite a bit of light will end up there. If you arrange the LEDs right, this comes pretty close to the ideal of having a thin curtain of light. Of course, you have to replace the existing battery system to power the LEDs.

It ought to work.... just haven't had time to try it.

How about a row of LEDs above the photodetectors spaced so the half power points of the radiated beams overlap, a diffuser, and an optical slit. Then shield from direct ambient relative to the detectors. Would require less power. IR to match the sensitivity of the probably phototransistor detectors would be ideal but you could see red ones. Once considered that and a fast processor on a precise 4 foot beam just for fun, never could justify the more precision/accuracy for my purposes. And something like Bluetooth so I could easily read the results on the bench.

Paper screens anyone?

Though I 'spect it's doable with plain paper and piezo sensors.