I finally ended up with a chronogragh. I took it out and got the speeds of 11 different loads from 4 revolvers. Actually, it raised a lot of questions in my mind. What does this actually tell me? I am mostly talking about how to analyze this info for reloading purposes. Where do I go from here?

I like to see how tight I can get my spreads. Means I'm doing a good job at the bench, and things are going well. If extremes are tight, accuracy is usually pretty tight too. That's about all I do with mine, but probably need to go a step or two farther as well.

X2

I also divide the standard deviation by the average velocity to get a percentage. If it's under 2%, that load's good enough for me. Under 1% is fantastic. In my admittedly limited experience, the smaller the spread, the smaller the groups.

Even more basic I use it as a "good enough" indicator for speed. We have small whitetail and thick woods. Why burn the powder and beat the wrists if a 44 load is going fast enough to expand the bullet and is accurate? Or with cast if it has enough muzzle energy, isn't leading, and is accurate then why push it? Obviously ballistic concerns come into play with longer range considerations.

I can also sometimes detect a sharp pressure curve before pressure signs show up in the cylinder or brass. If I'm keeping everything else the same and a step up in charge yields less or no increase in velocity from what is expected then you may be adding pressure and burning powder without much benefit. My comprehension of internal ballistics is primitive and I can't say why this happens, but I have experienced it in my limited handloading experience.

This is a good point. With shortguns there comes a time of diminishing returns. There is no reason to burn powder that doesn't yield an appropriate increase in horsepower.



While this is true, a little more speed can have a profound effect on the target upon impact and primary wound channel. Depending on the location of the hit it can mean the difference between DRT or a short jaunt.

All these years I didn't get a chrono because when I had the money I ended up buying bullets instead. I guess I was right all along,

I bought mine for archery and have used for yrs for that, but I used it for working up hunting loads for my 357 to determine wound channel size buy calculating the fps by meplat diameter. the thing with a chronograph is its a tool that you don't use often but its available when you want it.

I love mine! Me and the guys around here use it all the time. Archery, handguns, rifles, and even some shotguns and pellet guns have been shot over it!

I think its one of those reloading tools that isn't mandatory, but is nice to have.

A chrony is a must have for working up drops and point blank zero ranges. A person can use load data for reference but the speeds posted seldom match up with reality and the only way to know is to clock it.

Rod, what is a "point blank zero range"? Surely it can't be what it sounds like, is it??

Dohm,

There is no argument, you can can go your entire shooting life without one, safely. But for me, having has been almost mandatory.

I like to experiment, and have been doing so since my first "wildcat", the 375 JDJ. Sure there was a reasonable amount of published data out there. But when the Barnes "X" bullets hit the market, I had a choice, wait for others to publish, or forge ahead on my own. It was the same when heavy lead lead hit the market again. Doing it still, to this day with heavy lead in my newer 625PC in 45 Super and Auto Rim.

I think it a very important tool for us handgunners who are pushing the envelope in hunting. A lot of us are experimenting with guns, platforms and cartridges that operate at less than 50 or 60 K pressure. As such, flattened primers and even case head expansion are terrible indicators of pressure. As such, what are we left with, velocity as compared to some published data. Velocity will never be an absolute as to pressure, but it sure is a big ol' indicator, to be used with other tools.

The last time my chrony "saved" me was with going low with H110 in my lighter 454 loads.Started getting those 150 fps extreme spreads. I could not really feel them, or hear them as bad, but the numbers told me differently. And I was still in the published range of lower the lower end. But with my gun and component selection, as was already too low.

So Dohm, as to where you go now. Maybe nowhere. But one day you might get the urge to get frisky with your handloading, and you will be thankful you have it as a tool.

Craig

Good point! I notice I start paying a lot more attention to my chrony when I am messing around with the upper end of H110 loads.

PBZ is the distance you can shoot and still hit within a certain predetermined area without holdover. For deer hunting I use + or - 3" as my target area. For instance, with a 45 Colt shooting a 250 @ 1,400 zeroed at 110 the bullet will be no more than 3" above line of sight anywhere along its path and will be 3" low at approximately 135 yards so 135 yards is the PBZ and the distance one can shoot without holdover. A 7mm 120 grain @ 2,400 fps zeroed at 205 will also be no more than 3" high at midrange and will drop 3" low at 235 so a person can hold dead on from muzzle out to 235 yards and hit within the vitals area without worry. Most of my hunting guns are sighted in with this in mind.

WOW! Thanks for that! I learned something new with this. Gonna have to figure that out for my 500JRH. I just draw the line at 100 yards. If it is under 100, I will use the 500JRH or the 45 Colt. If its over the 100 yard line, I'll use the scoped 460 S&W.

But I like the idea of "knowing" the distances!

A chronograph is a wonderfull tool. As mentioned so far it will give you a host of pertinent information that is invaluable to the serious reloader. Nowdays a chrono can be had for a small amount of money compared to what I paid for an Ohler 33 many years ago. Being Scotish by birth I was looking for justification for the price paid. I must say it has paid for itself many times over in cost of ammunition saved using the SWAG method. A chrono gives speed which can be a base point for utilizing drop tables for trajectory which is a short cut to figuring out Point Blank Range. A chrono is a tool for measuring consistency. A chrono can help you pinpoint which component in a given load is detracting from said consistency. Even if that component is the shooter! When I look back at all the money spent on guns, equipment,reloading components hunting gear, guide fees etc, the chrono is the "best bang for the buck".

Don

Experimenting with the chrono is definitely a learning experience. I am trying a new bullet in my 44mag SBHH. It is a 270 WFNPB with a .345 meplat. [seems to me to be a perfect hunting bullet for that caliber] Using WLP primers and W296 I actually reached its limit approx 1190 fps. I than added 1 more grain of powder to that and the fps actually dropped almost 10 fps. I assumed the WLP primer was not hot enough. So, I tried Fed 155 the fps increased slightly to about 1240 fps average, low ES and super accurate. IMHO I am thinking I can get better velocity so, I swithched the primer again to CCI 350 and the velocity went up to 1290 fps. I believe this is telling me I can burn a little more powder with the CCI mag primer. Now I am going to up the charge 1/2 gr at a time to see if I get a velocity increase along with accuracy. I am actually trying to get in the 1350-1400 range [ideally] because that would make a great hunting load. [meplat x velocity divided by 4]