Help with Chrony

[M14MSgt]

Bought my first chronograph, a Shooting Chrony Chronograph F1

No instructions came with it. I know I can mount it on a tripod, but is there anything that tells you how to use it? How far from the muzzle, how to read the readings, etc.

[highvel]

The manuals are available at http://shootingchrony.com

[Unclenick]

I recommend the standard 15 feet from the muzzle that the gun magazines and load manual authors use. Instructions may not call for that much, but if you search on the subject, you'll find a lot of people get reading inconsistencies from being too close. One fellow with the .338 Lapua said he had to get back about 18 feet before false triggering was ceased.

If you own a laser bore sighter, that makes chronograph setup easier. Set a zeroed rifle on the bench and arrange the bags so it is sighted on target. Put the laser bore sighter in and turn in on. Go out to the tripod and find the beam by holding up your hand. Move the tripod and adjust the height until the beam hits the center of your palm when you hold your hand up in the middle of the screen area for both the front and back screen. I also like to put a small round bubble level on the unit between the screens to help adjust the tripod legs.

P.S., don't forget to remove the bore sighter before you shoot. That has blown up some barrels. Search the net for photos. I put a yellow range safety flag in the gun to remind me to pull the laser out of the muzzle before I remove the flag. If you have one of the cartridge-shaped laser bore sighters, then it prevents you from making that error. I've noticed quite a number of laser sighters on sale for under $30 lately.

[M14MSgt]

thanks. i dont see the need to get the printer. i am just startin out in reloadin.

[mrawesome22]

i am just startin out in reloadin.

I'm glad you have a chronograph. It is essential to load development.

[B.L.E.]

I agree with the at least 15 ft rule of thumb, in fact, with some magnum calibers, 15 ft is still to close to prevent false triggering by the muzzle blast.
I was using a Chrony at the range to measure the velocity of my .45-70 loads and even at 15 ft, the guy who was shooting some sort of magnum rifle on the next bench was false triggering my Chrony with his muzzle blast.

Before shooting, I make certain that the bore line is above the chronograph by aiming the rifle at the target and then bore sighting through the barrel, especially with scoped rifles.
It's real easy to shoot your own chronograph by forgetting that the scope is about 1.5 inches above the bore.
This also goes for AR-15 type rifles where the iron sights are a couple of inches above the bore line.

[totaldla]

Remember that you don't have to shoot close to the sensors to get a reading. Pick a spot mentally 8" or more above unit. Why? Because our eyes/brain have a natural tendency to try to line up with the horizontal edge of the Chrony. There's lots of dead Chronys to prove it.

Chrony's will live longer and work just as accurately looking upside down at a sheet of butcher wrap. Much less likely to shoot it. But your readout would be upside down too.

You'll know if muzzle blast is an issue when your 45LC clocks 6000fps.

[James R. Burke]

No doubt like suggested get that manual. I try to stay the same distance, and make sure your not getting false readings has mentioned being to close. I go with about 15 feet make a mark in the dirt so I go back to the same spot. I dont know if it matters but I try to shoot thru it in about the same spot each time. If you using a scope up close its going to shoot a little low, but it should not be very much. The last thing you want to do is blow a new crony apart.

[Slamfire]

I plumb mine with a Harbor Freight level. This also has a laser so, if it is overcast, I can more or less aim the chronograph at the target.

I have found that off axis shots produce wierd velocities. You have to shoot straight over the sensors. Powder residue will cause weird velocities. The further from the muzzle the less problems you will have due to powder residue and muzzle blast. I had to station my Chrono about 10 yards forward of my blackpowder musket. Any closer and the residue messed up the readings. I am also having the problem with sunlight illuminating the sensors and giving strange velocities. One day I will figure out how to shade the whole thing.

I start off with a "reference" load. My pistol reference load is a 38 Special load of 158 L 3.5 grains Bullseye. If I get something different from 760 fps, then something is misaligned.

Rifle load is usually a 308.

[rwilson452]

The first thing I did with my Chrony is replace the the metal rods with wood dowels. I then marked the "sweet spot" with a marker. both the high end and the low end and the middle as is is described in the manual. When lining up to shoot I align the scope with the center between the two high marks and the bulls eye of the target. With a nominal bolt rifle this will make the bullet pass in the sweet spot of the Chrony. If you shooting an AR with a scope mounted on top of the handle you will need to make an adjustment. Iron sights on an AR pose a similar issue. Drawing on a fuzzy memory the front sight of an AR is around 4" above the center of the bore. A bolt rifle with a large dia. scope will be 1.5 - 2 inches above. this distance is critical.

[GP100man]

since this pic I took a big square trash can & cut the bottom out of it & place the F1 inside , works great !!

I use skewers to replace the metal rods & take a black marker to mark sweet spot also !!

[IllinoisCoyoteHunter]

I protect my chrony. I have since replace the metal rods with wood dowels.

[GP100man]

ICH that`s ^^^^^ better than the brick I place in front of mine !!!!