Home Forums Hunting & Shooting Ask The Gunwriters Chrono, Yes or No

I wouldn't reload without one today. I was a reloader for a few years without one and was really guessing at velocity/pressure. I even use it today for checking various brands and styles of .22LR ammo. There IS a difference! But extreme spread IS an important factor in relatively low velocity ammo, either factory or home made. Some factory stuff is so bad in that regard, I NEVER buy factory except that which proves best in .22LR.

And in big bores, such as .45-70 and .458 WM, I've proven to myself that if I can get spreads down to less than 10 fps for 3 to 5 shots consistently, at pressures near max for that rifle, I've got a gem of a load that shoots sub-moa every time at the range when I do my part. And that gives confidence in the field. Here's one example of a 350gr TSX from my CZ550 in .458 Win Mag with a very long action and throat allowing Lott length: (Load taken from Lott data) -- 2746, 2747, 2746, 2749 and 2745. There's NO WAY I could guess that from numbers in a book -- especially when, as mentioned, "their" testing setup has nearly zero relationship to mine! I've written extensively on this in my manuals and blogs. That load would shoot 3 into +/-0.50" at the 100 yard berm unless I was having a bad day.

And, I could give numerous examples from other rifles of the same nature.

Bob

www.bigbores.ca

I quit using mine....
The load and rifle bullet comes out whatever it comes out....vol is what it is...and used acordnly....

Don't get me wrong it is a usful tool but it can also drive you nuts...
I talked to a guy at the barrel shop one day who was an avid sniper challenge shooter....champion as a matter of fact...he said most affordable croon graphs are not nearly accurate enoug...he uses range and math to calculate real vol....

And I quit reading right there.


Jerry

I see no problem with that. There are some people that think you cannot reload without one, but that's nonsense.

Some of these same people ignore published manufacturer's recommendations, keep adding powder and checking their chronos for unusual velocities. That is part of the method, but absolutely not the only thing you should be doing. And what is the condition of your chamber? What is the condition and size of the throat? Is it new or eroded?

Velocity is the best indicator for most shooters, but there is no guarantee that what you see on the display is correct, or a 100% indicator that the load is safe. Hence the warnings published by every bullet and powder company. Which chrono are you using? Is it reading properly? Chronographs are not created equally. Why are Oehlers so popular? They are expensive. Won't a Shooting Chrony do? Is your chronograph calibrated or checked occasionally? There are other factors as well. Are you adequately skilled at assembling cartridges? What signs are you looking for?

When someone experiments and deviates from published load data, they are going into unknown territory. Doing this takes some skill, and in almost all cases is unnecessary. Relying on chrono readings alone isn't smart. And other tools, like test labs or pressure test equipment, aren't in the hands of many reloaders.

Personally, I respect your decision. You are quite right when you say that the bullet will come out as it comes out. Use the data from the powder or bullet company, be happy, and watch critters fall over.

Blind adherence to published load data can get you into trouble also, don't think that you can chuck all caution to the wind just because you can read a cookbook.

Years ago I compared two loading manuals, Lyman and Nosler, for 7mm rem mag data. The powder I wanted to use had a 7 gr. difference listed max load for the 140 gr. bullet I was using. I started low using a chronograph and quickly figured out that the Lyman data was complete bullchit, I hit the listed max velocity in the Lyman manual 4 grains before their max, which was 3 grains over the max Nosler listed. If I had been following Lyman's data I'd have been seriously overpressure and the least, and probably into the blowing primer territory.

If you have a decent chronograph and you're at all familiar with it then you can pretty quickly tell if it's giving you good data. I can pull out my 6mm BR and shoot one of my 30.8 gr. Varget/105 Amax loads across it and it'll be 2860 +/- 10 fps at 70 degrees. If it isn't then something is wrong, but it hasn't lied so far.

Data from your own rifle is far more reliable than data from a min spec pressure barrel. Sure their velocities are accurate for that barrel, but that doesn't mean much in YOUR barrel. Far too much is made of supposed inaccuracies of chronographs, recent ones are very accurate and I'll trust them before I will some data shot in a pressure barrel 20 years ago with different lots of powder, brass, primers, and bullets.

Loading manuals are a guide, nothing more. Anyone that thinks they're gospel is fooling themselves, even the guys writing them will tell you that. Use a bit of common sense.

I agree with some of what you say. Nothing is 100%.

I did not talk about blind adherence to load data, but I did talk about blind adherence to what is indicated on the chrono display. Specifically, adding powder and watching velocities, thinking that the chrono is all you need to work up a safe load. It is only one of a number of tools and information required.

There have been reloading manuals that have published bad information, but that is the exception, not the norm. More people blow up rifles and suffer injuries because of improper reloading techniques or human error. Bad reloading data published in a powder or bullet company manual is rare.

I do not believe that anyone suggested that load manuals are the final word (gospel), but they are reliable. They test and publish instructions and warnings about working up loads properly. They take their work seriously. If you are unsure of what you are doing, they tell you to get help. No manual or company has ever suggested that their data is inviolate. I believe that reloaders are more likely to err than the techs that test loads.

WRT data from test rifles/universal test barrels, they do not produce the same velocity that your barrel produces, but the loads are safe. And modern test practices include pressure testing.

Most reloaders know that their velocity results will be different from published figures, but there is a caveat here. I know individuals who continued to add powder because their indicated chrono velocities were less than what was published in magazines or manuals. In these cases, relying on chrono figures was dangerous.

So, I will maintain that one does not have to use a chrono. It is a tool reloaders can use in combination with adequate training, a good manual, proper technique and a big dose of common sense.