Below is just my personal experience. Understandably, everyone needs and goals are different. Previously, I used a Shoot'n Chrony. The main drawback being the hassle of set up at a busy public range.

I've got both a Labradar and a Magnetospeed. I strap an old Weaver scope to the LR, and alignment to the bullet path is super easy. I use both the LR and MS when I fire foulers at the beginning of a shooting session to confirm I am getting accurate bullet speeds. They almost always agree to within 0.1% of each other, i.e. within 3fps for a 3000fps muzzle velocity. If they don't agree, I reboot each one and try again, at which point, they have always agreed. Then, I remove the MS and do my test shooting with the LR.

The cartridges I shoot range from .223 Rem to .300WSM. The LR is always able to pick up the .22 bullets, which are flat base (no experience with .22 boat tail bullets), and typically tracks them to about 50 yards. I have had the LR track .30 bullets up to 120yds. I have the Pietz accelerometer trigger, but never use it for rifle shooting because the LR pretty much never misses a shot for me. The Pietz trigger gets used for archery.

The LR is great because I get velocity on every shot while doing a rough (using 2-shot groups) OCW series of shots when developing a load. I am mainly looking for max pressure/velocity, but, since the LR doesn't touch the barrel, I get the groups for free. I then plot group size vs velocity and can quickly get a very good picture for how the gun works with that bullet and powder. I then go back and shoot 5-shot groups where I see tighter groups and a flattened velocity curve line up.

The only drawback for me with the LR, which, is as Mule Deer mentioned, is that I can't record my max velocities with my 22-250. Fastest velocity I ever recorded on the LR was 3929fps, and the 22-250 shooting a 50gn bullet will exceed that. The MS would be a benefit for these higher velocity cartridges.


Here is the basic set-up with a Kimber Montana .300WSM:

[Linked Image from photos.smugmug.com]



A graph of the results of a rough OCW test, plus four 5-shot groups centered around 68.5gn, with an M70 Extreme Weather:
[Linked Image from photos.smugmug.com]



Resulting 5-shot group from the above M70 load development:

[Linked Image from photos.smugmug.com]