Less than 1hr at 30*F. Seriously! I fired 14 shots on a new set of Duracell AA batteries and received the message that the radar couldn't arm because of low battery power. This was my first use of the unit.Get the USB Power Bank as it will eat through 6 AA in a couple hours or less.
I also learned that with 22 WMR cartridges, and reduced power loads in my .223, the muzzle needed to be within a couple inches, and right next to, or slightly behind the unit. Didn't activate with the muzzle 3 - 4" inches forward of the unit.
So there are some user nuances to be learned.
On the other hand, it read 22 caliber bullet velocities all the way out to 75 yds. Which I didn't expect.
This allowed me to determine a good B.C. value for these bullets using my ColdBore 1.0 ballistics program, which will be very accurate for at least for the first 100-150yds of use.
Same thing with my 338, 308, and 284 caliber centerfire rifles. I'm shooting new (to me) bullets in all three rifles. These lathe turned copper bullets don't have any Litz tested/confirmed B.C. values. By capturing 6 velocities over the first 75 yds of bullet flight, I was able to develop a G7 B.C. value for each bullet that's dead nutz on for the first 100yds of bullet flight. This gives me a good starting point. I expect these B.C. values will need to be tweaked down slightly for 500-1,000 yd use. Only measuring drops at longer yardages will tell the full tale on their B.C. values at reduced velocities. I plan to reprogram the unit to record velocity at 20yd increments in order to capture downrange velocities out to 100 yds with the larger caliber bullets.
It's a lot easier to haul and set up than my triplicate optical chronograph setup. Another big advantage - it's not light intensity sensitive. From November thru February, I lack sufficient outdoor lighting for reliable use of my Oehler chronographs, because the sun is so low in the sky at my northern Alaska latitude.
So there are some nice features. BUT..., purchase the lithium power pack if you buy the LabRadar. Unless you want to have to install 6 new AA batteries after every 14 shots fired. I'm glad I did.