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Just received my CED chrono & infared screen. My first chrono, never even used one before.
What should I be focused on when collecting data from strings?
What are good numbers?
What goals do I need to achieve?
Any info on chrono's would be greatly appreciated.
I need Chrono 101.
What are you trying to accomplish?
Some people use the chrono in order to max out the speed of a round they are reloading.
Some people use it measure the extreme deviation of a string - the difference in speed between rounds fired. Less deviation typically means better accuracy.
Fastest rounds do not typically mean the best accuracy.
For accuracy you want low es (extreme spread) and sd (standard deviation) numbers....means the rounds are launching at the same speed..within a fps spread.....for long range, it may not effect your horizontal spread, but a big difference in sd or/and es will show up in your verticle string.....What most of the bench shooters look for is 15 fps or better es.....sd around single digits.....hope this helps...also, when working up a load, you'll hit a point where more powder doesn't raise FPS...but does pressure...means you need to back down a little to hit your accuracy "node" (sweet spot)....rsbhunter
Be careful not to shoot the thing, and be aware that muzzle blast can knock it slightly crooked, giving errors when you miss one array.
+1 on this. Try to set your chrono up the same way every time. I set mine at 10ft measured with a tape and put a level on the chrono each time. Bigger calibers will have more muzzle blast and might need to be 12 or 15 ft away to keep the blast from affecting accuracy readings. 3 shot strings can give a fair representation of velocity, but are pretty much useless for es and sd. Long strings make for more accurate data.Quote:
Originally Posted by us920669
Not quite sure. Thats why I am asking.Quote:
Originally Posted by Rick_W
What would be good choices to work on with a chrono?
I currently load 9mm, 45acp, 223 for my Colt HBAR & will be loading for my new Savage 10 FCPK in 223.
Never load at max, never felt the need. Would like to load for accuracy.
What should I work on for the full benefits of a chrono?
Any links for Chrono 101?. All I could find are sites that review or talk about a specific chrono.
Quote:
Originally Posted by ah141nj
all of them... i would take your loads your using for each now and see what the the es and fps of them are. if your satisfied with those numbers shoot away if not go higher or lower