A chrony question: Are yellowed diffusers harmful?

[rquack]

I got out my chronograph yesterday to begin prepping for the arrival of a new rifle and the load development that goes with it and to my surprise i found all of my diffusers [skyscreens] have yellowed. Yup, its been in the box a lot longer than I care to admit; but will I need to replace these items in order to obtain accurate velocity data from my unit?? Can anyone help me out based upon their prior experiences with a similar problem on their own equipment?? Can these units be painted white to preserve their usefulness?? Or do I just bite the bullet and order replacements??

 

[DrMike]

Yellowed or not, the diffusers will work just fine. They will not affect the registration of passage of the bullet across the screens.

 

[rquack]

Thanks very much for the fast and knowledgeable reply. I appreciated it.
Rob

 

[FOTIS]

Not an issue. mine are orange!

 

[ROVERT]

Not an issue. mine are orange!

Show off.

Just kidding. Nice chrono, FOTIS.

 

[Guest]

Fotis,
How does the Chronograph pictured compare to the F1 Chrony? Just curious.

Thanks,
Don

 

[FOTIS]

1. No errors that are not identified
2. Less sensitive to light or lack thereof
3. The Chrony will do 95% of this one.

 

[Guest]

What make/ brand is that one and projected cost one could expect?

Thanks,
Don

 

[FOTIS]

The one in the picture is this one.

Made for a limited time only. In my opinion the best in the world (non-pro versions)

http://www.oehler-research.com/model35.html

 

[Guest]

Thank you Sir.

Don

 

[alpinecrick]

Fotis,
How does the Chronograph pictured compare to the F1 Chrony? Just curious.

Thanks,
Don

Fotis's chrono is the Oehler M35--considered the gold standard of chrono's for 20+ years. The M35 probably has the best screens, and offers the third "proof" screen to detect possible erorrs. They were discontinued a few years back, but Oehler has offered a limited run for $575--that includes a tripod, 4 ft rail, and carrying case.

CED M2 is a close second, I don't think the screens are quite as good as the Oehler. Faster clock speed and the crystal ocillates faster than the Oehler, which hypothetically makes it more accurate. Because of the faster operating speed, CED claims they don't need the longer rail (the longer the rail, hypothetically the better the accuracy--I've seen some guys running 6ft rails on the Oehler's), so the CED comes with a 2 ft folding rail--which is more convenient. The M2 can store multiple shot strings, calculate Hi, Lo, Avg, SD, and a few other things I don't pay attention to. $199 You can also get the IR screens and the rechargable battery for the screens. The IR screens make their own light, and don't care how bad the light is. With the IR setup you can shoot indoors, in a snowstorm, or in the dark. ~$150

A lot of guys like the PACT Prochrono--which I think has been recently replaced by the Pro XP. $230. When I bought a PACT in the 90's, I got so pizzed at it I threw into the ditch behind the barn--for all I know it may still be there. The new Pro XP also offers IR screens--I don't know the price.

The Germans have come out with a new Chronograph--the PVM-21 which uses IR screens. From the looks of it, at least some of the electronics are out front with the screens--at $700-$800 for the unit, I'd hate to think of what it costs if you shoot it..........

The Shooting Chrony's: let's just say they're cheap.....that way when you shoot it--intentionally or otherwise, you won't feel so bad......


Casey

 

[Guest]

Casey,
I appreciate the reply and insight on the Chronographs. I learned something from the info. I'm currently on my second F1 Chrony due to shooting the dumb thing with the 35 Whelen. It failed the 225 AB test that day. :mrgreen: Your right I didn't feel so bad as the replacement cost wasn't like 575.00. But the saying you get what you paid for applies with Chronograph's too. Someday I may extend myself and invest in a M35.

Thanks,
Don