Chrony question

[dawg11]

So I thought a chrony would help me to find the limitations of my air guns . So I searched all over and ended up with a new Gamma chrony with the ballistic printer for $105 , going to send it in and have it upgraded to Gamma Master for $43 . But wanted to test drive it before I sent it in for the up grade . So this morning I set up the chrony and got out my 1377 . Put 5 shots each thru it  460 - 470 FPS with 5 pumps and 720-740 with 10 pumps . Seems like the right numbers . Then I got out my PCP's thats when the numbers got weird . First was my 2240 .22 cal that I converted to PCP got 2561 - 1512 - 2098 . Got similar numbers (didn't write them down ) with my QB78 thats converted to 9mm . I was the same distance away from the chrony with all three guns (6 feet) . As much as I wish they were shooting that fast I'm 99.9% they are not . so I assume I'm doing something wrong . Any ideas?? I did not hook up the printer during this test .

[MJP]

Fluorescent lights nearby? Too little light or shooting too near of the chrony, air blast messing the readings.

[Roadworthy]

Bob, you're not providing enough information to analyze.  Where were you shooting - indoors or outside?  What kind of lighting was used?  If inside it could have been incandescent, led, or fluorescent.  If outside it could have been direct sun or shade.  The time of day could also have an effect.

Chronographs tend to be pretty light sensitive - Chrony brand more than some others.  They also depend on contrast between the pellet and the background more than a specific light level.

By the way, you "stole" your Chrony for that price!!

[dawg11]

I was out side in direct sun light , no clouds at all . 11am this morning . No other lights anywhere . If it matters I had the diffuser shields on also . Its just strange to me that with the pumper (1377) the numbers were plausible maybe even correct . But the numbers were no where in the ballpark of correct with the PCPs . I even moved farther away for the last shot with the PCP and it still was like double what I thought it could be .

Yeah I know I stole it , I it was 155 but every time i tried to check out it said we'll knock off $$ if you apply for this card so I did . In the end I got two new credit cards to shred , LMBO . but they took off $50 . The printer alone goes for for about what I paid for both units . Shooting Chrony says the upgrade to master is only $43.

[Roadworthy]

I can't account for the difference between guns with the same Chrony at the same time.  I usually shoot over my Chrony (Alpha Master) at about three feet and the readings seem good.  I only have springers, though.

If the sun is not pretty close to directly overhead the sky shades (or whatever) may allow direct sunlight to hit the sensors.  This will prevent proper operation.  When the sun is not directly overhead I like to get in the shadow of a building or a tree.  The shade works fine if I have a clear view of the sky above (open shade).

All in all I have found the Chrony to be a bit picky.  I only got it as opposed to the Pro Chrono due to the remote readout of the Master series.  With the Pro Chrono I'd have to purchase accessories and drag my laptop to the shooting bench.

I'll live with the Chrony.