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Old July 19, 2012, 02:38 PM   #1
Red Dog
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Join Date: November 28, 2010
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I'm thinking about a chronograph

I've been reading up on them and trying to figure out are they really useful.
Are shots fired above the screens? Surely not in the opening above the
instrument. I'm also reading about printers and lighting conditions.
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Old July 19, 2012, 03:22 PM   #2
Bailey Boat
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Yes, the shots are fired directly above the unit, within the "triangle" formed by the sky screen rods and the skyscreens.. Aim accordingly.....
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Old July 19, 2012, 03:52 PM   #3
Edward429451
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Fire below the screens and above the unit. After shooting my 2nd Chronograph () I put a couple wraps of electrical tape on the rods about 3/4 of the way up from the unit, so it was a reference point for me to sight between and I have not shot my 3rd chrony yet.
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Old July 20, 2012, 08:32 AM   #4
jmr40
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You can spend as little as $100 and get pretty acceptable accuracy. Some guys have tested the $100 units side by side with more expensive models and have found them to be pretty darn close accuracy wise. You are paying for features. Some allow you to print out info or even download to your computer. I'm content to simply write down the readings on a notepad between shots with my $100 chronograph.

Yes, you shoot above the screens and light is needed. The 2 screens are an exact distance apart. When you shoot your bullet casts a shadow on the sensors as it passes over them and a timer measures the time it takes between the sensors. That time is converted into fps.

As light conditions change you may get slightly different readings. The intensity and angle of the sun can cause minor differences in velocity readings. In low light, such as cloudy days i don't even use the sunscreens.

You also need to be pretty consistent with the distance you place the chronograph from the gun. You will get faster readings if at 10' than at 20'. Too close and muzzle blast will shake the unit and give inaccurate readings. I try to get as close to 15' as possible every time.

And yes, it is not uncommon to shoot your chronograph. Your barrel is 1.5"-2" below your sights and the bullet is that much lower at very close range. You need to be aiming 4"-6" higher than the unit to be sure of missing it.
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Old July 20, 2012, 09:08 AM   #5
Skimp
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Yea, I shot my first Chrony up. Put a 9mm straight threw the front and out the back. With this second one I place a target behind to be a little more civil.
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Old July 20, 2012, 09:52 AM   #6
Red Dog
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Check out the link.
Attached Images
File Type: jpg chrono.jpg (40.0 KB, 27 views)
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Old July 20, 2012, 09:58 AM   #7
osageid
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Yes ^
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Old July 20, 2012, 12:40 PM   #8
a7mmnut
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Yep, between the display and the sky screen. Hold very still while testing shotgun loads!

-7-
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Old July 20, 2012, 09:46 PM   #9
tobnpr
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Useful, yes.
Mandatory, nope...
Just purchased my first (Chrony Alpha Master).

For our long range shooting, knowing the actual MV (rather than estimating) speeds the process of getting dialed in at long range when punched into the ballistics program.

Also, even though knowing how to read pressure signs keeps us out of trouble, it's good to know if you've pretty much maxed out- even though you might not be getting the visible signs (flat primers, hard extraction). If your MV is indicating max pressure- you know you're at the end of the road.

While it's good to be able to verify max velocity, more often than not, it's not the most accurate load- in my experience. While some guys seem to get the tightest consistency at/near/beyond max, that's rarely been the case for me.
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Old July 23, 2012, 01:39 PM   #10
ragwd
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I havent shot mine yet,lol. but I set up with a bore laser and some cardboard at the chrono just to make sure.
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Old July 23, 2012, 02:00 PM   #11
g.willikers
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How high above the sensors you will have to send the rounds depends on the available light.
Bright cloud cover, that diffuses the sun light, is best for getting good readings without putting the chronograph in danger.
Be extra careful when using scopes or high mounted sights, though.
As for being useful, they are indispensable for safer and accurate reloading, and also for knowing velocities, for figuring ammo ballistics.
Sure beats guessing.
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