deere tech Report post Posted October 3, 2014 Will a chrono read different speeds for the same load set up under different light conditions? Should it read the same on a bright sunny day compared to a cloudy hazy day. ? Share this post Link to post Share on other sites
oz31p Report post Posted October 3, 2014 Yes. Different lighting conditions will affect the reading Share this post Link to post Share on other sites
willhunt4coues Report post Posted October 3, 2014 Yes it will. If you don't want light effecting the reading look at the Magnetospeed. It attaches to the barrel and uses magnets to read the bullet. This can be used in sunshine, darkness, cloudy days, rain, ect. I have always got the same reading no matter what time of day it is. A little on the pricey side but one of the most accurate reading chrono and fastest to set up and take down. Share this post Link to post Share on other sites
lancetkenyon Report post Posted October 3, 2014 You have to consider what powder you are using too. Some are very temperature sensitive, and will change velocities as temps go up or down. As much as 70fps in some cases. So the loads you shot in December could be a lot faster in July, or loads you shoot in the morning can vary if you leave your ammo in the sun at noon. Share this post Link to post Share on other sites
deere tech Report post Posted October 3, 2014 I kept everything pretty constant as far as temps go. the only difference was the light. when i first cronographed the gun it was bright and sunny, i just recronographed it before i head to wyoing and it was cloudy and hazy and the overall average speed for five shots was 60 fps faster. thanks for your input i thought i was going crazy or i did something wrong while reloding. Share this post Link to post Share on other sites
lancetkenyon Report post Posted October 3, 2014 One of the reasons some chronos have the white shields on them. You don't needs them on cloudy days but you do on sunny days. They read when an object breaks a light barrier. Share this post Link to post Share on other sites
deere tech Report post Posted October 3, 2014 So what reading do you think was the most accurate. i used the white shields on both the bright day and the low light day. Share this post Link to post Share on other sites
lancetkenyon Report post Posted October 3, 2014 I would stretch it out to at least 400 and plug in your numbers to come up with a more reliable ballistic chart. 400+ yards will help you correct your actual muzzle velocity in most ballistic programs. I would not solely rely on a chronograph myself. To me, a chrono just gets you close, and shooting at distance gets you closer to a true ballistic calculation. 2 Share this post Link to post Share on other sites
Becker Report post Posted October 3, 2014 ^^^^ I agree with this statement. Share this post Link to post Share on other sites
