How often to chronograph?

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Just to put this out
I've chrono'd my pellet gun.
It came in @ just under 1000 fps.
Then I added peanut oil into the cavity.....the .177 went all over the place.
I must admit that it did have a nice crack to it.
 
I chrono when working up loads, for velocity and consistency. For the long range stuff I chrono the same load during diferent temp ranges to give the ballistic software some data points to interpolate.

For my handgun defense loads, I chrono the factory stuff, then build a reload using the same bullet at the same MV range for practice.
Just worked up some XTP loads for this.
 
Of course a chrono won't tell you pressure.
But it can help give you an idea of whats going on, and for example if your muzzle velocities are higher than the book MAX
it's not certain but a pretty safe guess that your pressures are higher than book also. NSTAAFL.

I need to load for power factor and I like to be about 128/130 since I'm shooting minor.
It's nice to be able to tell I am in the area I want to be. I can fell the difference between 125 and 140 but for example 120 feels close to 125/128
Nice to now if your powder is temp sensitive vels go up as it gets hotter and down when colder, Some powders are reverse sensitve, faster when colder
 
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A chronograph can be a useful tool when used properly, but it is not an essential piece of equipment.

I've addressed this in detail in other posts, but every light-sensing chronograph I am familiar with has no provision for external calibration. That means the velocity it reports will only serendipitously be correct. It should be "in the ballpark", but it will almost certainly not be "correct". It is useful for comparing with other readings taken by the same chronograph to ascertain relative velocities of projectiles and consistency from round to round.



When I am developing a load, every round goes over the chronograph; some are shot with more emphasis on getting the velocity data and others are shot with an emphasis on accuracy, but all data is collected. The data may not prove to be useful, but if not collected, it cannot be retrieved later.



When developing a load, for each incremental increase in powder charge, I load 10 rounds. Five are shot over the chronograph with a focus on getting readings. The second five are shot for accuracy with the only chronograph-related concern being to not shoot it.



Once I start developing a load, I don't pay any attention to the velocity predicted by the book. I will know whether I achieved it once I get my data back to the house and start evaluating it. And the reality of life that I have yet to have a load deliver the same velocity published in the book; mine are always slower.

It's kind of like the old Kenny Rogers song, "You never analyze yer data while yer sittin' at range; there'll be time enough fer analysis when the shootin's done."

If the fact your 16 inch barrel AR is not delivering the same velocity as published data compiled using a bolt action rifle with a 20 inch barrel or a universal receiver with a 26 inch barrel and that's going to cause you to go off trying to figure out how to get to book velocity, then by all means DON'T buy a chronograph.


  1. Since the "real world" velocity is rarely the same as in the published data, the chronograph lets me know what "neighborhood" I have actually ended up in.
  2. It provides a check on whether or not my components are producing consistent results.


No AR for me. 1-9 twist 22'' barrel bolt action 223rem. :)
 
I loaded for many years, never owned a chronograph or a case gauge and was happy.

Once I began shooting competitively I acquired both, now that I know how much time they save, I own many of them.

I don’t chronograph every round but I do know what a load will do in a given firearm at different temperatures.
 
Max velocity does not tell you anything about pressure. Some barrels are faster than others, fact. I have one barrel that's very consistent at being 100+ fps over what most books post. But if you have enough load data books you can find one that will be close to what your getting. I also have another one that is consistently 100 fps slower than most book. A lot of variables come into play on what makes a barrel fast or slow. My match barrel have a polish that's will ravel any mirror. My general plinker has a pretty rough bore which made it slower than most. If you pull 5 load manuals I dought you will find any that actually match each other. In rifle you will find large spreads of 1-2 gr or more depending on caliber. Then if you look at what the mfg used in the testing, 100% it's not your gun. So take it with a grain of salt.

A crony is just another tool to give you info on what our doing. It's up to you to interpret it. I would by no means use it as a pressure indicator. If so you will be leaving a lot on the table. Which is critical if your shooting long distance.

I went 40+ years without a crony and produced very accurate safe ammo. It's just a tool like any other tool.
 
I chrony each new load, but only as I develop it. I don't recheck it every time I open a new bottle of powder, leaving it to the manufacturer to keep those lots at least reasonably standardized. I probably would THINK about re-chrony of new lots if I was shooting long range competition...but even then, it wouldn't likely be necessary if the accuracy of the round didn't change. If I did rechrony in those instances, I'd probably be looking more at changes in the variation than in the fps of the round.
 
I chronograph every time I make a new load(not every round) ... I normally do the full work up on a particular load ... once I am satisfied with the proper brass fit in my chamber, the proper OAL for that bullet/gun, the pressure(no pressure signs), suitable accuracy ... I will then run at least a ten round "shoot" over the chronograph to see if the load is within my expectations ...knowing that different temperatures and condition affect the results ... Here in Southern Georgia you can have 20 degree weather and the next day 80 degree ... if it is summer time 100 degree days are fairly often ... All the gathered data is recorded in my "data" book along with any other information about the load including gun ...
 
I guess another question is as long as you have an accurate load what's the point of chronographing?

Good point, some of my best groups have been achieved by focusing on technique without the distraction of velocity. But personally I would never develop a load without a chronograph - there's just too much useful information available for the modest investment.
 
what's the point of chronographing?
Bragging on internet guns and shooting forums.:D
Nah, just kidding around. But I'll tell you what - years ago I worked up a "very good" mule deer hunting load for my wife's 7mm-08s using 139gr. Hornady SPs and Winchester 760 powder. It's an accurate (3 shots in less than an inch at 100 yards from either rifle) load, and my wife, our daughter, and now our grandson have killed a lot of deer with it over the years. Then I got a chronograph, and found out that 139gr Hornady is only going a little over 2600fps from either of my wife's rifles, when according to the book it's doing a little better than 2800fps. I was disappointed until I remembered how much chicken-fried venison steak I've eaten due to that load.:)
Nowadays, I mostly use my chronograph for working up handgun loads. But I could get by without it - I did for 20 years or so.
 
View attachment 776437 I have been very pleased with this. $100 or less. Setup on a tripod and shoot from my bench. Just make sure that you set it far enough away to avoid muzzle blast interference.
I use the same one. I set it up every trip to the range, which these days is nearly once a week. Nothing wrong with more information imo.
 
I've done a lot of load workups, mostly in pistol, but I'm doing more and more rifle lately. When working up loads, I almost always use a chrono.

I try to do accuracy and velocity at the same time. Why not, I don't see much advantage in separating the two, but that is my opinion.

In looking at my load data for 45acp, I noticed a historic trend that showed my pistol was generally the most accurate with loads in the 700-725fps range. Interesting to note, and sometimes I may look for that velocity when working up new loads.

For either rifle or pistol, if I get low standard deviations, to me that is a sign that the bullet/powder/charge/firearm are all playing nicely. If I get a large deviation or extreme spread, I generally see that as the powder not operating in a good pressure range for the given bullet and firearm.

More often than not, the velocity curve (velocity vs charge) will be non-linear and exhibit "steps" or flat spots on the curve. If an accuracy node is noticed in the same region, this is great. You have a load that is accurate, and the velocity is not likely to vary much with a slight change in charge dropped, or possibly temperature.

Having said all of this, I started out without a chrono and found good loads initially without one.
 
I feel my chrono is an essential part on my reloading equipment for pistol & rifle rounds. I chrono nearly every precision rifle rnd I fire because I am ardently chasing single digit velocity deviation. A worthwhile but elusive goal! With my pistol reloading I document every powder I use with every bullet I use in every gun I own. When supplies become scarce again (and they will), I can match available powders, bullets & primers to my stored data and still have something to shoot. It's also a lot of fun!
 
I feel my chrono is an essential part on my reloading equipment for pistol & rifle rounds. I chrono nearly every precision rifle rnd I fire because I am ardently chasing single digit velocity deviation. A worthwhile but elusive goal! With my pistol reloading I document every powder I use with every bullet I use in every gun I own. When supplies become scarce again (and they will), I can match available powders, bullets & primers to my stored data and still have something to shoot. It's also a lot of fun!
That is what I have done as well. I don't get all hung up on single digit standard deviations with pistol loads (20 or less is ok) but for rifle, I do like single digit SD. Single digit extreme spreads just makes my day when it happens.
 
Almost all my ammo is sent across the chronograph. It's timed as I shoot for accuracy.
I am a very lucky man in that where I shoot, my only limitations are wind and that the sun is up.
I don't have to worry about other shooter being in front of me...setting targets and so forth.
I shoot pistols at 25 yd with a rest, iron sighted rifles at 50 yd (old eyes, ya know) and scope-sighted rifles at 100 yds.
The "window" on the skyscreens of my Oehler M33 are big enough for several targets to be set so I can shoot a bit testing before I reset.
Competition ammo doesn't have a chrono in front, but everything else does. Copetion ammo has already been tested or it's not competition ammo.
Have fun,
Gene
 
I'm debating on getting a chronograph to check some loads and wondering how often you guys use it? Say you have your good load and it checks in at say 3200fps with say 10 shots do you call it done and that's all the testing you do for that load? Do you chronograph for each lot of powder?
You questions are fairly rifle-centric and I am a pistol shooter. But the way I see it the chronograph is valuable enough for load development that even if you do use it for nothing else it's a smart purchase that also improves safety. I've now got two chronos - first a Caldwell and a new Competition Electronics ProChrono as pictured above with the bluetooth module. Take my advice and buy a CE unit the first time..
 
My first chronograph was an old Ohler that you had to turn a dial,write down the numbers and go to a chart to get the velocity.It was slow,and a real bear to set up,but it was very enlightening for me when I saw what a difference some factors made in velocity.I chronograph when I have my load giving me the accuracy I'm looking for.I also use it to watch for temperature variations.I usually try to get several guns to the graph at one shooting session so I don't have to set it up so often.I think a chronograph is one of the most valuable tools in my reloading toolbox.A good ballistics program and known velocity can save a lot of time when I am working on hold overs and wind drift.It can't measure pressure,but if the velocity suddenly goes high,you can catch a bad situation before it happens.
 
I know this is a month old, but I thought I'd offer my experience, and maybe open your mind to exploring different aspects of reloading.

A few preliminary statements to be made:

There is more than one way to skin this cat. I really don't care to participate in a BS argument where a bunch of guys drop in their 2 cents about "I've reloaded for 50yrs and never owned a chronograph," nor one about the legitimacy of different principles behind different methods of optimal barrel time, OCW, Ladder, velocity flats, etc... Different methods can work, and further different methods can work "WELL ENOUGH" for their respective shooter. Some folks don't have very high demand of their loads, so they can live with lower expectations, and when they get a 3/4" group at 100yrds, nothing else matters, as the load does what it needs. Some guys might not be aware of the BLISS that is found in shooting within a node, vs. at an anti-node, and those guys will live a life EITHER ignoring the "flyers" in their groups, or one of despair where their loads just don't shoot well - some of these guys even go back to factory ammo and don't reload any longer... Alternatively, any variable distance competitor NEEDS to know their velocity, and how environmental conditions change it. I competed in Service Rifle for a few years without a chronograph, and I burnt far more cost in ammo trying to find a load with low vertical dispersion at 600yrds than I would have paid for a chronograph. Bought the chrony, and my scores were better. So the value of a chronograph became obvious for me. See the end here for my newest experience in how spending money on a chronograph is saving me even more money...

I'm debating on getting a chronograph to check some loads and wondering how often you guys use it?

When I only had an optical chronograph, I despised the burden of setting it up, lining it up, running cable back to my position... I'd take my chrony along a lot, and rarely actually shoot over it. Now I have a Magnetospeed and a Labradar, and there's rarely any excuse to not chrony every shot I take in practice.

If I change lots, I chrony. If the environmental temp changes, I chrony. Change primers, bullets, brass, changing neck tension, etc... If you chrony along the way, you'll be able to see when your barrel life starts fading - you'll lose velocity as your throat erodes.

For this reason, despite the higher cost, I REALLY recommend either the Magnetospeed or Labradar, preferably the Labradar, since the POI shifts with the Magnetospeeds, except of course for the high cost of the Labradar. I did fine with a Prochrony Digital for many years, a Beta, and a couple others, but the set up really puts me off, so again, I just don't use them as much as I want because of it. The Magnetospeed Sporter is competitively priced against skyscreen optical chronographs, but it does come with the POI shift. The V3 has more adapters, which is an advantage to some guys, and it stores more strings, so you can do your data transfer when you get home instead of writing at the range... Labradar lets you set up easily on the bench and doesn't affect POI, but it does cost a lot more, and it's a bit bigger to haul around. I keep my Magnetospeed Sporter in my range bag at all times and use it when I'm casually shooting, whereas I use my LabRadar when I'm doing development, but it does mean I own more stuff....

Say you have your good load and it checks in at say 3200fps with say 10 shots do you call it done and that's all the testing you do for that load?

This isn't how I develop loads from the start, so no, I don't get 10 data points and call it good...

Do you chronograph for each lot of powder?

Yes. When I'm diligent and responsible, once I find a proper load for my barrel, I'll buy enough powder of the same lot to last the entire life of that barrel. Otherwise, I chronograph again any time I change lots.

Say I'm doing a load workup for a rifle do you chronograph each load first or find what's most accurate first then see if your pushing it too fast?

Don't worry about specific velocity. There should be a ~100fps window where your round will perform the task needed, so your task is to find a consistent, precise load in that velocity window. If it's 3250 or 3350, it won't matter, as long as it's CONSISTENTLY 3340 +/-5fps and it groups nice and round, and small, you're groovy.

Do you try and keep it under book max fps or right on?

Book velocity is irrelevant. Nothing more than a guide post. Kinda like saying an American man should weigh 170lbs and be 5' 9"... Not many actually hit that number.

I guess another question is as long as you have an accurate load what's the point of chronographing?

Accurate load, precise load... What are you using to determine precision? For your upcoming 300yrd matches, all you need is a load which shoots tiny at 300yrds, so keep your mind in that context. But... What happens inside 300yrds is often very different than what happens outside of 300yrds, but 300yrds is far enough for the little details to matter. At short range (300), a guy might see a half inch group with a 40fps ES, and a half inch group with a 10ES. At 1,000yrds, 40fps spread will reveal itself as vertical dispersion, no matter how small a round shoots at 300 (40fps ES is over 6" at 1,000yrds in my 6 creed, would be a lot worse in your 223!).

Chronograph data should accompany all of your OCW or load work up. Don't focus only on finding small groups - you need to find a forgiving powder window, find a "node." If you find a nice, round group, AND it has little to no velocity shift across 3 or 4 charge weights, you know you're in the hunt.

I've also used this load development method of late. It does work. I started with loads I'd developed the old fashioned ways, then tested this method below to see if I could replicate my loads with so few shots. Sure enough, I found the node in the same place, but in 10 rounds instead of 100. I haven't fully converted, but I'm certainly a believer in saving barrel life, and starting with velocity flat spots does let me get to the end point with fewer rounds fired. For a round like 6mm Creedmoor where barrel life will likely be 1500-2000rnds (800 before it starts falling), it's nice not wasting 10% of my barrel life on load development.

 
For many years I shot at 4 IPSC competitions a month. The only chronographs I saw, or used were at the match to determine major or minor caliber. Decades of reloading have passed and I still have no need for a chronograph. My competition is just myself and I am only concerned where the bullet goes, and not how fast it got there. The information provided in the manuals is all I have used.
I do understand how useful a chronograph can be, and it's nice too see them affordable to many shooters, just not me.
 
For many years I shot at 4 IPSC competitions a month. The only chronographs I saw, or used were at the match to determine major or minor caliber. Decades of reloading have passed and I still have no need for a chronograph. My competition is just myself and I am only concerned where the bullet goes, and not how fast it got there. The information provided in the manuals is all I have used.
I do understand how useful a chronograph can be, and it's nice too see them affordable to many shooters, just not me.

How often are you compensating for 5-6mils of drop in IPSC? Handguns aren't rifles.
 
I know. I should have been more clear. I mentioned what was my only use of a chronograph. I still don't use it for my rifles.
They definitely have a place, but not everyone needs one.
 
Since I have a Magnetospeed which straps to the barrel, I'm not inclined to use it unless I'm in load development mode. If I had a Labradar and knew how to use it, I'd probably be inclined to set it up more often. Most of us have the occasional flyer, or whut? shots, a handy chronograph might provide insight as to why.

I guess it depends on whether a shooter views shot velocity as data, or information.
 
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