Chrony Data

[CZDave]

Just got a chrony last week and took it out for a test run to see how my reloads are doing. Everything went well and I now have some averages for the various recipes I shot that day. Question is, what to do with that information? I see how it would be important for working with max loads, but so far Ive been perfectly happy in the low to mid ranges. So is there anything else for which I can use this information?

Thanks!

 

[1SOW]

Pistol Load types and speed issues: SD/hp expansion, plinking, competition with power factor (PF) requirements, supersonic/subsonic.

Your group size can/will improve/get worse as speed changes. You can tune your load to your pistol for tightest groups.

 

[Rule3]

I like to see small extreme spread and low SD (standard deviation) which will indicate that you loads are consistent. This is usually how well you powder charge is measured and if you are using the correct load.

Basically if you sample 10 shots and they are all very close to the average than you are good. You can then fiddle with loads to see how much it takes to go up or down.

I ran some 125 gr LRN 9mm today and a difference of .3 grs of powder made a 100 fps difference,

 

[minnesota]

Are you working with pistol and rifle? For the rifle, it is very important to have a low extreme spread and S.D. for long range shooting. The lower the both the better the groups on long range shooting.

 

[amlevin]

I also use my Chronograph to help determine the best load for the cartridge/bullet combination. I have found that when I hit the "sweet spot" of low "Mean Average Deviation", SD, and ES, I have also found a load that groups real nice at varying distances.

I have a favorite load for my .308 that consistently tests with a Mean Average Deviation of 5 fps or less on any given day. Also my most accurate load with nice little "ragged" holes at 100 yards. 3/4" at 300 yards also if I do my part.

 

[Clark]

I like to record all load data and range reports in Thunderbird email.

I use gmail now, but I keep Thunderbird around to save information.

Not only the velocity from the chrono, but also scan the targets, put in the quickload predictions, put in gun smithing to do's, pictures of the guns, weight of the guns as tested, what the wind speed was, what scopes were used, what benchrest was used, ect.

It is just like a lab write up.

 

[k4swb]

While I have found using a chronograph to be fun, I have also found the info mostly useless for short to moderate distances. I've shot some really great/small groups with ammo that the figures were not very good and some really crappy groups with ammo that looked great on the chronograph results.

Velocities may help in figuring trajectory but ES/SD/AD and such rarely mean anything as to group sizes.

A load that looks really good on the printout MAY shoot excellently but then again it may not.