Problem measuring MV for .22

[chromatica]

I have had trouble measuring the muzzle velocity for .22LR using my Caldwell chronograph. The chrono doesn't reliably issue readings. I assume the projectile shadow is just too small to be perceptible to the optic sensor. Anybody else out there who has run into this? Is there anything I can do to get reliable readings, or do I need to move to a Labradar?

 

[mac86951]

I have had trouble measuring the muzzle velocity for .22LR using my Caldwell chronograph. The chrono doesn't reliably issue readings. I assume the projectile shadow is just too small to be perceptible to the optic sensor. Anybody else out there who has run into this? Is there anything I can do to get reliable readings, or do I need to move to a Labradar?

Lighting and distance from sensors are the common culprits.

1.5" above sensors is ideal; and full sunlight. Cloudy days mess up readings.

Labradar; not susceptible to lighting issues.

 

[shoot4fun]

I just got my Labradar and have not even had it out to the range but my shooting buddy has had one a while and is having trouble getting it to read 22LR. So, not sure you will fare better with that. M have an older model PACT and it reads 22LR fine. So does my Magnetospeed V3.

 

[JPeelen]

In my experience its not a problem of lack of sensitivity. The shadow of a much faster 5.56 mm is much more difficult for the instrument. My recommendation:
Placing the chrono too close to the muzzle may actually confuse the electronics. It should be at least 10 feet away.
If shooting inside, keep in mind that fluorescent lamps actually go on and off 60 times per second (too fast for the human eye) and make any chrono unusable. Be sure that no such lamps are switched on.

 

[Ledd Slinger]

Which Caldwell? I'm assuming it's the cheaper model?

I use the Caldwell Ballistic Precision "G2" chronograph and have never had an error reading on a shot. All my varmint rifles are 20 cal using small 34gr and 39gr bullets. A good LED light kit makes all the difference in the world. Plus the inverted design of the G2 also helps to avoid bad readings in adverse lighting conditions. The lighting kit also allows use indoors under florescent lighting.

Many reviews confirm Labradar can have a lot of trouble with readings on small projectiles. Which again was confirmed by the comment from member 'shoot4fun' in this thread. So pretty sure that's not the answer. Would probably just end up being an expensive mistake.

I would maybe look into upgrading to the Caldwell G2. Very nice for the money and very accurate. Or at least get a light kit for the regular Caldwell chronograph. A good light kit can make a chronograph a LOT more reliable.

Caldwell G2 link:
https://www.midwayusa.com/product/1016955798/caldwell-ballistic-precision-chronograph-g2

Standard Caldwell Chrono light kit:
https://www.midwayusa.com/product/327456/caldwell-ballistic-precision-chronograph-light-kit

 

[jpx2rk]

I've used a Magnetospeed sporter on my 22lr and got consistent reading, close to what the published (?) data on the box was, and have had no issues on a 204R or 3 different 223's. May have to adjust the settings a bit, but the Magnetospeed display will show an error message, make an adjustment and try another round. Try and borrow one if possible.

 

[Depart123]

You can do some things to help the eyes see the bullet. Taping paper to the top and letting it droop down the sides will allow the sensors to see the bullet without being confused by excess light. A more involved way to really make it uniform is to put the chrono in a cardboard box tunnel and put battery powered LED lights in the tunnel with the chrono. Make sure the lights are in a position to fully illuminate the sky screens.

 

[Tempest]

I've used a Magnetospeed sporter on my 22lr and got consistent reading, close to what the published (?) data on the box was, and have had no issues on a 204R or 3 different 223's. May have to adjust the settings a bit, but the Magnetospeed display will show an error message, make an adjustment and try another round. Try and borrow one if possible.

Ditto. I've chono'd every possible .22 round and all have a reading with Magnetospeed.

 

[Ledd Slinger]

Yeah but magnetospeed is no good to use 'during' load development with centerfire rifles. It has been proven many times in many reviews that point of impact and group sizes can change from having the magneto on the barrel while firing and then firing with it off.

Hard to beat a good quality optical chronograph WITH a light kit like the Caldwell G2, PACT, or Oehler. Sure they take an extra minute or two to set up on a tripod, but they are accurate, can take readings on any size projectile, and never change the accuracy or POI characteristics of a load.

 

[Outrider27]

We use PACT and Magnetospeed, and both have proven reliable with 22RF ammo. We have seen POI shifts with the Magnetospeed, but never an increase in group size.

 

[boltfluter]

My Oehler 35 will do this very easily, and no problem with the 17's either.

Paul

www.proprecisionrifles.com

 

[Zero333]

I have a RCBS chronograph and it never missed a 22lr reading.