Labradar Tolerance of Obstructions

[AlanF]

Have just taken delivery of Labradar and looking at doing some 100yd testing on the house block. Being a smallish block, the "range" threads between or over various fences and structures. I notice in the manual it warns against obstructions within about 5m of the line of sight to the target. Has anyone experienced problems of this sort? How much obstruction will it tolerate, and what problem is caused (e.g. poor accuracy, failure to measure)?

[KHGS]

I have had issues with longish grass in the proximity of the firing point at my home range. This will result in no shot registration.
Keith H.

[williada]

Alan, I had to lop a few tree branches out that were too close. Also had problems when shooting out from under cover. Like Keith I had no shot registration. Careful aiming and alignment of the Lab Radar did help. On a light flimsy bench the recoil with heavy guns can bounce the Lab Radar if it is not supported properly and change the alignment. Also went to permanent electrical supply via transformer as it chews through batteries. Had mine a few years now with no glitches. Play with the sensitivity to get improve results. Perhaps we could see a better aiming method attached to the Lab Radar in the future to ensure alignment where sheds or structures or vegetation could spoil the activity.

[AlanF]

Thanks Keith and Dave, I'm concerned about things like bolt heads and fence wires NEAR to the line of sight giving false radar reflections and confusing it. Anyway, I hope to give it a try over the next day or two, so will keep you posted.

[KHGS]

Thanks Keith and Dave, I'm concerned about things like bolt heads and fence wires NEAR to the line of sight giving false radar reflections and confusing it. Anyway, I hope to give it a try over the next day or two, so will keep you posted.

My advice also, use a powerbank to run it not batteries,
Keith H.

[bsouthernau]

Perhaps we could see a better aiming method attached to the Lab Radar in the future to ensure alignment where sheds or structures or vegetation could spoil the activity.

A piece of one of those hexagonal-section ballpoint pens stuck in the notch on the top of the labradar works well as a sight. Minus the refill of course

I run mine off one of those mini jump start packs.

[AlanF]

I have AA 2500mAh rechargables, so may try that first.

[Pommy Chris]

I am not convinced of the reported accuracy of the Lab radar. IMO placement can cause errors in reading. I have a pic on my phone also when the Lab radar shooting with Darren with 155's recorded a shot velocity of 5186 fps!! As the action was not in pieces my guess is the lab stuffed up
Chris

[AlanF]

I am not convinced of the reported accuracy of the Lab radar. IMO placement can cause errors in reading...

I'm sure it does. It's a matter of learning the finer points of correct setup. I will be using it in conjunction with a magnetospeed initially, and trying different positions and settings till there is good agreement.

[pjifl]

Agree that the internal battery option is not the best. We always use an external power pack. But my observations are that low batteries means it is less likely to work at all. Aiming is a real problem and most missed readings were cured when aimed more carefully with fresh batteries. I think this can be worse depending on terrain.

On accuracy, we had three LRs side by side and were stunned that the readings never deviated more than 1 f/s from each other.

If you go into the memory SD, you can find actual track data on each bullet. This lets you see at what distance the LR locks on, and how, as the bullet moves away, it sees fewer successful echoes. The reading you see on its display is an average - extrapolated back to zero distance - derived from maybe 100 echoes.
I have never seen a ridiculously high reading.

Putting it alongside a MagnetoSpeed - we showed that the Magnetospeed is far less believable. Often out by 30 f/s. but erratically so.
For a lot of work absolute accuracy does not matter. But for measuring consistency, I believe Magnetospeed has a precision an order of magnitude worse than LR. The most erratic are the old optical ones. They depend a lot on the lighting variations.
Peter Smith.

[AlanF]

Whew! Thanks Peter. As with most new and expensive things I didn't jump in with Labradar, but have finally taken the plunge. In fairness to Magnetospeed, I've never had reason to believe mine is erratic, and that has included testing in parallel with other chronos. As you say, absolute velocities cannot be verified by anything we can afford to buy, but who cares, its shot to shot velocity comparison where we want precision. The only application in our sport needing good absolute velocity measurements is for policing of energy and velocity limits, and even that can be managed by allowing margins of error.

[KHGS]

Slightly off topic, but I think relevant, the actual velocity is of lesser consequence than the SD or extreme spread of velocity! Too many chronograph users tend to focus on the high end velocities. This is often where the nodes narrow down and the load can go out of "tune" more easily. Nothing to be gained by pushing the envelope to gain 50 to 80 fps, but much can be lost in that pursuit. Some early tests 15 years or more ago seemed to indicate a closing of extreme velocity at the longer ranges. As I recall these tests were conducted over two Oheler chronographs one at the muzzle and one set up at a 1000 yd target, this was a small test sample and should not be considered to be any more than indicative, but food for thought nonetheless. There is no doubt that a hell of a lot goes on with the flight of the bullet in that 100 yds between 900 & 1000 yds. I sometimes think that we may be going the wrong way by pushing the bullet weight and BC past a certain point in our quest to gain better 1000 yd results....but I am NOT a ballistics expert, just a gut feeling is all. One other small thing I try to do with load development is to do this when ambient temperature is between 22 and 28c all these ramblings for what it's worth.
Keith H.

[Pommy Chris]

Agree that the internal battery option is not the best. We always use an external power pack. But my observations are that low batteries means it is less likely to work at all. Aiming is a real problem and most missed readings were cured when aimed more carefully with fresh batteries. I think this can be worse depending on terrain.

On accuracy, we had three LRs side by side and were stunned that the readings never deviated more than 1 f/s from each other.

If you go into the memory SD, you can find actual track data on each bullet. This lets you see at what distance the LR locks on, and how, as the bullet moves away, it sees fewer successful echoes. The reading you see on its display is an average - extrapolated back to zero distance - derived from maybe 100 echoes.
I have never seen a ridiculously high reading.

Putting it alongside a MagnetoSpeed - we showed that the Magnetospeed is far less believable. Often out by 30 f/s. but erratically so.
For a lot of work absolute accuracy does not matter. But for measuring consistency, I believe Magnetospeed has a precision an order of magnitude worse than LR. The most erratic are the old optical ones. They depend a lot on the lighting variations.
Peter Smith.

Hi Peter,
Have a look at this then, just us on the range and this is a 155, rather quick IMO.
Chris

[Pommy Chris]

IMO the issue with these is calibration or lack of it. The Police need their radar calibrated every few months. We are hoping for 1 or two FPS accuracy forever it is not going to happen.
I disagree too with the magnetospeed IF it stays tight on the gun I doubt there will be any accuracy issues but standard strap works loose in a few shots.
In Canada with Rutland team we tested shooters with both Magneto speed and Lab radar, spread of velocities was far higher with the Lab, either it was picking up something the magneto was not or it was throwing the odd curve ball which is what I think. Changing slightly the angle alters the speed, a little to recoil moving it is going to change velocity shot to shot. This can be proved by picking up next doors shot much lower speed than it should be. IMO slight changes in angle or shooter moving like in FTR or target rifle is going to alter results.
Either way my pic above proves these are far from infallible.
Chris

[KHGS]

IMO the issue with these is calibration or lack of it. The Police need their radar calibrated every few months. We are hoping for 1 or two FPS accuracy forever it is not going to happen.
I disagree too with the magnetospeed IF it stays tight on the gun I doubt there will be any accuracy issues but standard strap works loose in a few shots.
In Canada with Rutland team we tested shooters with both Magneto speed and Lab radar, spread of velocities was far higher with the Lab, either it was picking up something the magneto was not or it was throwing the odd curve ball which is what I think. Changing slightly the angle alters the speed, a little to recoil moving it is going to change velocity shot to shot. This can be proved by picking up next doors shot much lower speed than it should be. IMO slight changes in angle or shooter moving like in FTR or target rifle is going to alter results.
Either way my pic above proves these are far from infallible.
Chris

I know of little that is infallible!!! Even rocket science is not infallible !!!
Keith H.