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Can the data help you make a more accurate cartridge? If so how? I know my reloads are not the most accurate, but I can still hit the 8” steel plates at 25 yards. Some tweaking and test firing can help dial in a more accurate cartridge. My first thought is a chronograph will let you see the FPS in your particular gun from factory loads. Do you try to replicate this in your hand loads? Thanks
 

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Most chronographs will do some computations for you too - like standard deviation. That more or less tells you how consistent your powder charge is. I use mine for factory loads to test performance from different length barrels. The numbers you see from the manufacturers are almost always overstated, and I want to know the truth for the weapon I'm carrying. Particularly with my PT145. That round is already slow, and I wanted to make sure I was getting sufficient velocities for reliable expansion of hollow points. I've heard 7-800 fps for 45 acps, and the standard velocity rounds were way to close to the line. +P on the other hand nearly replicates standard velocity performance from a 5" barrel, so that's what I carry. Thank you, chronograph. It also told me my old Gamo pellet gun is due for new springs, as its velocity has fallen off from over 1100 fps to 850. All kinds of stuff you can do with them.

Even if you've just got a low end Shooting Chrony, you can still get string information out of it - max velocity, minimum, standard deviation, and some other stats. You just have to add a remote button - or you can make your own pretty easy. Here's a link to a thread on the subject - if you flip through it you'll see a couple ideas for DIY remote switches. Chrony upgrades
 

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dbeardslee makes excellent points. While not the begin or end all for accuracy consistency plays a part in accuracy. The only way to test speed consistency is with a crony. My most accurate loads usually are +/- 2% or less.

I find a crony very helpful in working up full power loads (mostly rifle) sometimes signs of over pressure do not show until you are way over. With my chronograph, I can compare to other loads and see if I am approaching the limits.
 

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Good reloading manuals give velocity and chamber pressure for starting and max loads. They will give barrel length etc that their data came from. Taking those things into consideration I shoot 5 shot strings when working loads. Look at velocity for SD and to see how it relates to the load data. Look at the gun to see how clean or nasty it is running etc. A lot of powder will not burn clean until it gets in the pressure range it likes. You can have two guns that are chambered for the same round yet one does better or worse than the other with the same load. Being able to watch velocity and the SD gives you another part of the picture. The fastest loads are not always the best. Different bullets work better in some guns than others. A good example is two Trackers I have in 44 mag. The guns are alike in every way, barrel length and all. One likes 210 grain bullets the other 240 grain. They are the most consistent with the bullets and loads they like best. Chronys pay for themselves when you use them. You can even find the bc of bullets using a pair of them.
 

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A chrono is the only way to really tell the velocity you are getting. You rarely get what the load book shows due to differences in chambers, leades, components, cylinder gaps, pressure barrels vs real barrels, and many other little things. I have one 1911 that is always 50+ FPS faster than my other two.

As posted, it will also tell you how consistent it is as far as velocities go. This is not very important with pistols at close range, but is critical in rifles at 1000 yards. As always, on target results are what count, and many loads with poor ED & SD numbers can shoot really well. Naturally we all like to see those numbers as low as possible, but you cannot get caught up in chasing numbers and lose track of on target results.

A chrono is a good tool for reloaders, and we are fortunate these days to have many choices and price ranges. The $100 (On sale) CE Pro Chrono Digital has worked very well for me for many years. Naturally the pricier ones have more features.
 

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Chronographs are also good for getting good guesses on terminal performance. Want to know if your hollowpoints will still expand reliably out of a short barrel? Chrono it. The same goes for soft points in rifles.
 

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Discussion Starter #7
Leaning toward getting one thanks for the info. I have not had much time to research them, maybe in the next couple of months I will have time.
 
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