Chrono Questions

[Walrus]

I've been reloading 9mm and 45 ACP since June. Never had the opportunity to chrono any of my reloads until yesterday. Was at the range with my buddy and he had his Chrono.

I have some left over Remington UMC in both 9mm / 45ACP that I wanted to use as a 'control group' then I was going to test my reloads. The following are the results we got.

9mm REM UMC, 5 shot string, S&W M&P9
1196, 734, 737, 1902, 742

9mm My Reloads
1081, 1078, 1061, 1075, 1081

45 ACP Remington UMC, Springfield Loaded 1911
Err, Err, Err, Err, Err (wouldn't read)

45 ACP My Reloads
687, 716, 687, 697, 703

I shot a few more 9mm REM UMC and got wild spreads like before. Shot another string of REM UMC 45's and it wouldn't read.

I guess my questions are: what might I have been doing wrong, or what might have been the issue with the UMC ammo throwing wild numbers or not reading at all?

Just looking for input from those more knowledgeable.

 

[Tim67]

Looks like your reloads are better than the factory loads.

 

[tactical723]

Chronos are very sensitive and pick up shadows and sunlight traces. The best scenario is to set
It up where there is consistent sunlight or consistent overcast. Never setup under a metal or reflective overhang
Or under a tree. It appears that some stray movement or
Light was interfering with the reading to
Cause inconsistent readings and error.

 

[Walrus]

Thanks for the input.

I guess it could have been the light.. It was overcast, we weren't directly under tree's but we weren't in a field either. Just weird that it would get consistent readings on my reloads and the factory stuff was spreading so badly and/or not reading at all. All the shots took place within about a 10 minute window.. Back to back strings of fire if you will...

 

[Storm52]

Light changing is the culprit. If the cloud cover changed, allowing ambient light to increase then you will experience weird spreads or errors. I built a box for my chrony to eliminate or at least diminish light as a factor.

 

[Walrus]

I had no idea they where that sensitive to changing light patterns.. Good info, filed away under 'learned something new today'.. Thanks again..