Home Forums Reloading Big Game Rifles HELP

Got my gun back from the smith after a re-barrel. Working on load development. I shot a particular load 2 days ago, sunny, hot and humid, 82F out. gusty winds. Got the velocity I was looking for, accuracy didnt get a fair shake.
I loaded 5 more of the exact same load, the exact same components to test for accuracy and my velocity jumped 200fps!!!!!. Only difference was it was 45F today and low dew point, heavy clouds and started raining. Absolutely no signs of pressure. Actually shot pretty accurately. Big question, is my chronograph malfunctioning due to conditions from bright sun vs heavy clouds. Never noticed it before and didnt have a different gun to double check it. Very concerned about the jump, but bolt was smooth, no extractor marks or anything. What do you all think?
Chronograph is a caldwell.
Loads are 338RUM 210 swift Scirocco2, new rem brass, Fed 215 primers, 5 shots at 100 grains, 3 shots at 100.3. Max is 102 in the book. Velocity 2 days ago was 3200, today was 3370 average. very confused. only thing different is daily conditions. seating depth and all components is the same.

What powder are you using?

The light has been known to create different readings.

Think we've found the problem.



Yep, esp. with the cheapo units.

I've compared my Oehler 35 vs Caldwell - they might be close on a bluebird day

Thanks guys, that's a relief. So now I need a new chrono. No idea what to look for. Suggestions please.

The two best answers are Oehler 35 and LabRadar.

Magnetospeed

Thanks, I'll be getting a new one.

I have been very happy with my LabRadar.
Duane

I really like my Magnetospeed.

I've been watching the videos, and like the premise of the labradar. Price is a little tough to swallow. Is it worth it?

Another vote for the Labrador. Easy setup, very accurate and will not alter your point of impact like a magnetospeed will.

Weird. My Chrony won't hardly read at all in direct sunlight, but does fine in the shade or on a cloudy day.
I do usually have some other gun and load that is a known quantity with me just to check it, however.
Might buy one of them newfangled labradars someday..........

I can't speak to the Labradar but when I bought my Oehler back in the mid 80's it cost abut what a new rifle cost and I asked my self the same thing. Now over 30 years later the Oehler cost me about $15 dollars per year to know what my loads were doing. It was a bargain!

Blacktailer, you spoke my mind really. That is typically how I roll. Good to hear someone that thinks the way I do.

Most of the Ohlers for sale are from people who bought a Labradar.