Is there a method of verifying BC using data from labradar?

I’m working up a load for a 338 250 gr Rocky Mountain ULD with a claimed G1 of 0.842.

You might be able to do it on my range. Often, with the long pointy bullets, you need even more distance than what I have.

If you know for a fact your chrono is giving perfect numbers, and your scope tracks perfect, or you can hold elevation perfect, run it down the range and look for a discrepancy.

If at X distance you're low, tweak the BC down, and look at what the calculator gives as new corrections. Often times, MV can be off by 50 to 100 fps, and the calculator and DOPE are still matching to 400 yards. So 500 to 800 is where one can really true up their calculator. Wish I had a longer rifle range.

No, not really. The longest the LabRadar will register is 250 yards. That's not far enough to calculate a true long range BC. You can set up the chrono numbers to register 5 readings from the muzzle out to 250 yards, but you need a longer range to determine a better BC.

I would reverse calculate your BC, and use a G7. I would use the chrono to give you a velocity reading on each shot. Zero your rifle at 100 yards, dead on. Estimate your come ups to get you on target out to 600, 800, and 1000 yards. In the field, record your actual drop needed to get exactly on target. Pull up the nearest airport environmental data at the time of your range shooting, and enter all this info into your calculator. Enter in the exact environmental conditions and bullet velocity. Change the G7 BC value until your come-ups match your field data. That's the method I use to "back into your BC". I would use a G7 also.

George at Rocky Mountain keeps his BC's fairly accurate from what I have seen. He makes a good bullet!