LabRadar problems?

[dickn52]

I'm guessing that the recorded differences are in the ammo and not the Labradar. I say this because the radar still records your shots consistently. Temp changes create changes in results as stated.

 

[Ledd Slinger]

Chronograph test today. The difference between them is surprisingly small. From previous data, I was doubting my lab radar. It appears to be pretty solid, but did show a tad of deviation different from Dave's. More than just temperature affecting velocities is my conclusion so far, I would have to say density altitude probably is effecting more than just external ballistics. Amazing to me is how I've seen rifles stay in perfect tune, yet have a different muzzle velocity, sometimes by quite a lot. Thanks @Torge for putting the results on a file.

Tom

The LRs were both reading consistently and significantly faster speeds... Now if he could conduct this same test on another date in the near future under slightly different weather conditions, and maybe even a different location, we might may be able to draw a small conclusion as to whether or not the LRs are reading correctly.

You are probably right that there is more going on than just temperature changing velocities. Problem with using radar is that you can start experiencing propagation effects on the waves from the atmosphere conditions and interference from the earth itself. Then you couple that in conjunction with the actual atmospheric induced speed changes of the bullet and things can start looking pretty odd. I think this may be why some of you are left scratching your head from time to time.

 

[Berger.Fan222]

It helps to pay attention to the signal strength and get the alignment right. External battery power is also important.

Optical chronographs are also sensitive to alignment issues.

 

[Ledd Slinger]

If you guys look at the far right column (notes), you will see I intentionally mis aimed my unit at times. To our pleasure, there looks to be more forgiveness there then I would've thought before actually testing.

Brandon, the oheler was out in front 12-15 feet. Although I agree, it should've been a lesser margin slow. But it did move the same linearity as different loads/rifles were shot across it.


The beauty of the lab radar is it can work while shooting prone. My next step will be connecting the dots at distance, and all the while gathering data on each individual shot. I hope to get that accomplished next weekend, smoke/fire restrictions depending.

Tom

I see. Good point on the Oehler being out front. That would account for a good portion of the velocity difference. Being able to shoot prone with a chrono is definitely an advantage. I might be able to set up for prone with my Caldwell G2 on my manfroto tripod by laying the legs all the way out and dropping the center column all the way over on its 90 degree axis, but that would be a pain in the butt to set up.

Perhaps the LR is showing true speed variations that you and Alex have been getting. Would need to have a second chrono on hand to verify each time which may be a pain. Perhaps the loads are staying in tune due to using a load in the center if a ladder test? I know you guys wouldn't run a load on the upper or lower edge of a sweet spot.

 

[BenPerfected]

Thanks for the honest feedback, glad I didn’t buy a Lab Radar. Assuming your loading is consistent, what do really learn with any chronograph that improves accuracy?
Ben

 

[Miril]

I like rl33 in my 7mm

Agree

 

[Hoodoo]

So I got started on development for a fresh barrel today. Check out the top end of this 2x powder ladder. I'm not saying my lab radar is wrong, but I'm sticking with my opinion that 1000 yard paper don't lie!


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I believe in positive compensation....... but ain't no way 75 fps es is going in to 2" of vertical at 1k lol.

That is the exact reason I stopped caring what my chrony read. If it shoots at 1,000 yards, I could care less what my ES is.