First time using a chronograph

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crazysccrmd

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I finally got around to buying a chronograph (Chrony F1 Master) and took it out to the range this morning. I shot some 22lr over it to check it out since that was the only factory ammo I had. The Winchester bulk pack is labeled at 1280fps and gave me a five shot average of 1203fps, at 71° and 44% humidity according to my phone.

All the 5.56 loads were with LC brass, Tula SRM primers and at 2.26" length. I used a Lyman powder drop and can tell it doesn't give consistent drops using stick powders. I fired five rounds for each barrel length.

IMR 4064, 25gr
16" 2779fps, SD 39, ES 98
10.5" 2518fps, SD 19, ES 48

IMR 8208XBR, 24.5gr
16" 2746fps, SD 46, ES 121
10.5" 2443fps, SD 51, ES 111

H4895, 25gr
16" 2908fps, SD 68, ES 142
10.5" 2531fps, SD 27, ES 66

For my two main hunting rifles I hand measure each load on an electric scale and they were much more consistent.

8x57, 17" barrel
150gr Hornady SP, 50gr H4895, 2632fps, SD 17, ES 30
175gr Sierra SP, 48gr H4895, 2413fps, SD 9, ES 16

250 Savage, 22" barrel
100gr Nosler BT, 35gr H4895, 3009fps, SD 11, ES 21
100gr Partition, 34gr H4895, 2895fps, SD 7, ES 14


Having this ability to see my actual velocities is awesome. Using an online estimator for velocity put both my 8x57 loads a little over 100fps faster even after compensating for the reduced barrel length.
 
The thing I like most about a chrono is that it brings the science forward in reloading. I loaded for years without one, but now it is the third thing out of my bag when I shoot a new load.

Advice: Don't focus too much on what factory loads do in your world. Factory specs are extremely controlled. I doubt we will ever achieve the factory specs in the field. What is more important is consistency from bang to bang. If you are satisfied with your consistency, you are more than halfway there.

Good Luck to you in your latest addition of fun.
 
Congratulations on your chrony.
Here are some hints:
  1. Replace the skyscreen metal rods with wooden rods. That way when you hit them, the wood shatters and is easily replaced rather than the metal rod breaking the plastic housing they stick into. I super glue 3 chopsticks together with 2 back-to-back and one in the middle as a support.
  2. If you get erratic readings, move the chrony out a bit. Muzzle blast tends to give false readings. Fortunately a false reading is easily noticable. You won't get a false reading that is only 100 fps off, it's usually double or more of the expected MV.
  3. When the sun in low, you may have a tougher time getting good readings. For me, sunset was a pain so I don't bother bringing it out if I'm going to shoot late in the afternoon.
  4. Sometimes if you paint the bullet black with a magic marker, you might get better reliability in the readings. The chrony looks for a dip in the received light to trigger the clock.
  5. Always double and triple check your muzzle height above the chrony, especially with scopes. It's also a good idea to set up your gun, go on the other side of the chrony and look down the barrel to make sure of the bullet path. I shoot at a range and do the setup during ceasefires and we have to insert breech flags to ensure and unloaded gun so I'm sure I'm safe when I look down the barrel of my gun. Some people also put markers on the skyscreen sticks to indicate optimum height above the sensors.
  6. Bring a notepad and write down the velocites. Yes, the chrony stores strings, but with the convoluted button pressing required, it's easy to mess things up without a manual.
 
Anyone here *not* have numbers written all over their chrony manual/instructions?

great advice already. Also make sure its folded out flat.
 
You could make a printout of the instructions as I did at first.
Now all I need to know are the commands to read out the string calculations and the other 2 most important functions:
1. Clear all readings from the string
2. Erase everything and reset all to factory defaults <- the most important one! :)
 
Happy with mine, too. Wouldn't consider developing a load without it. Made a sunshade out of black posterboard to tape to the sticks when the sun is shining from the side. Sure beats trying to use a magic marker on the bullets! Seems to me I did read somewhere that the chrony is consistently 15 fps slower than the oehler though. Might be worth checking out.

Correction: FASTER than the Oehler. Sorry
 
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I miss mine (except for the last time), just haven't picked up another one yet. I believe there are 2 types of chronograph owners. Those who have shot their chrono, and those who are going to.
 
Thanks for all the tips and suggestions.

I shot the 22lr first to take the edge off being nervous about shooting the chrony. That was definitely not what I wanted to do the first time I used it.

For each load I testes I wrote out a 3x5 note card with the load info, caliber, barrel length, etc, prior to heading out. It helped me keep it organized and on track. I would just write down the velocity displayed after each shot in the proper line.

Next time I'll take my FN49 8mm out to see how much velocity is added shooting the same loads with a 6-7" longer barrel.
 
SFreed said:
I miss mine (except for the last time), just haven't picked up another one yet. I believe there are 2 types of chronograph owners. Those who have shot their chrono, and those who are going to.
Click to expand...


That's why I like my MagnetoSpeed. No way of shooting it really.

Congrats on the chrony. I know I love knowing my MV. Makes it really easy to use a ballistics calculator to figure out drop and whatnot.
 
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