chroni not picking up 17wsm, tips on how I should set it up.

Iv got a Prochroni like the link below

https://www.outdoorsupplies.co.nz/Co...noDigital.html

I have no issue with it with any other caliber but when trying to get the speed off the 17wsm it seems like it dosent want to read it passing thru
seagull wings on or off

I have a sneaking feeling that If I do everything right it will work just fine

so is it better in a bright day or the less light of the evening/cloudy day?

is there a distance found to be better?

can I put it(chroni) at the target 100m then just work backwards with the bc to get muzzle velocity

any tips and tricks for this little round or is my chroni just not up to the task

Zero at one or two hundred

Measure projectile drop in inches at the 300 and 400 yrd target

Adjust FPS in your ballistic calculator so it matches the inches of drop on target, this gives you the validated FPS

This way negates the need for a chrony

Quote:

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Originally Posted by Bill999

Iv got a Prochroni like the link below

https://www.outdoorsupplies.co.nz/Co...noDigital.html

I have no issue with it with any other caliber but when trying to get the speed off the 17wsm it seems like it dosent want to read it passing thru
seagull wings on or off

I have a sneaking feeling that If I do everything right it will work just fine

so is it better in a bright day or the less light of the evening/cloudy day?

is there a distance found to be better?

can I put it(chroni) at the target 100m then just work backwards with the bc to get muzzle velocity

any tips and tricks for this little round or is my chroni just not up to the task

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I shot lots of 17wsm over the exact same Chrony on sunny days with no issues. Weird.

It shouldn't be an issue with bullet size, my older version registers air rifle pellets okay.

How far above the sensors is the bullet passing? Might need to shoot a bit lower..but not too low!

Cloudy days give less weird readings.

clean the lenses!

Quote:

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Originally Posted by Beavis

I shot lots of 17wsm over the exact same Chrony on sunny days with no issues. Weird.

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id say this is user error
it was in the afternoon on a cloudy day heading to evening

same day 280 rem worked perfectly every shot
300wm same thing picture perfect

ill have another go at it but after near ten shots and no reading I thought id better leave it for another day

Quote:

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Originally Posted by Cigar

It shouldn't be an issue with bullet size, my older version registers air rifle pellets okay.

How far above the sensors is the bullet passing? Might need to shoot a bit lower..but not too low!

Cloudy days give less weird readings.

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ill try that
its a jard ar15 looking thing with a cantilever so im always telling the owner that rule number 1 for using the chroni is - don't shoot the chroni

How you off for ammo? Saw a couple of boxes the other day in a shop

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Originally Posted by charliehorse

How you off for ammo? Saw a couple of boxes the other day in a shop

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The mate that owns it is good, he got a stack of it years ago and have only recently got a rifle to run it thru, cheers tho

Hi Bill999, I have an old Shooting Chrony that doesn't work great on dull days so I bought 2 $8 led tent lights from The Warehouse, these have a magnet on the backside so I taped a panel washer to the underside of the diffusers to stick the lights to. Much cheaper than the proper light kit and seems to do the job.

Quote:

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Originally Posted by 7mmsaum

Zero at one or two hundred

Measure projectile drop in inches at the 300 and 400 yrd target

Adjust FPS in your ballistic calculator so it matches the inches of drop on target, this gives you the validated FPS

This way negates the need for a chrony

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This. I do it to double check the chrony isn't tellin porkies, doing both to cross reference each other reduces the effect of variables both ways.

Clean the lens and change the battery seems like a good place to start.

Quote:

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Originally Posted by Bert 71

Hi Bill999, I have an old Shooting Chrony that doesn't work great on dull days so I bought 2 $8 led tent lights from The Warehouse, these have a magnet on the backside so I taped a panel washer to the underside of the diffusers to stick the lights to. Much cheaper than the proper light kit and seems to do the job.

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awesome Iv got a few similar lights I can give that a go with

do the LEDs face directly at the two sensors chroni?

Another trick with some optical chronies is to build a ply or cardboard "box" to shield the sensors from light from the sides so they only recieve light from directly above.

Quote:

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Originally Posted by Marty Henry

Another trick with some optical chronies is to build a ply or cardboard "box" to shield the sensors from light from the sides so they only recieve light from directly above.

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Like a tunnel? Ie cut the bottom out of a cardboard box and put it on its side with the chroni inside?


Sent from my iPhone using Tapatalk

Yes, in the center directly above the sensor, might try the cardboard above and on both sides myself so there's a consistent light source not affected by the sun of any reflection.