New ladder test (JLA)

[ChuckR]

Hi Guys,
In my last post I did a ladder test with my AR15 at 50 yards, Had trouble reading the results and was told here that I needed to do it at 100 yards minimum and 200 yards was better. I did these ladder tests at 100 yards as there are no 200 yard ranges near me. Here is what I shot.

CHART A
.223
Federal case
Hornady 55grn FMJ bullet
Winchester WSR primer
Powder- Varget 24.1 to 26 grns in .1 grn increments.
AOL- 2.20 inches.

Chart B
Everything the same except;
Hornady 55 Grn FMJ soft tip.

What do you guys see in my charts as a good powder range?
Thanks for all your input.

Chuck

[steve4102]

When I do my makeshift ladder tests I use 3 shot groups of each load and I use larger increments than .1gr. For example, in the 223 I will use .3gr increases in charge and in larger cases like the 300 WSM I will use .5 or maybe even 1 full grain.

Have you read this?
http://optimalchargeweight.embarqspace.com/

[woolleyworm]

I would load 10 rounds ( two 5 shot groups ) of each of the following and test

Chart A - 25.6gn

Chart B - 24.7gn

If they group well, then that's when I'll start adjusting OAL length/seating depth. There may be slight charge adjustments after messing with seating depths also.

[rcairflr]

For .223, I also like to do my ladder test with one shot at each weight and .1 gram increments. It's almost the same as doing 2 shots at each weight.

[JLA]

.1 gr increments are a bit close together but I believe you have good enough results to extraspolate a good shooting load.

Chart 1 looks like you have 2 sweetspots. Which is good because in this case you can choose hot or cold. Shots 3/4 are your low end sweet spot, choose either or since you cant split .1 gr in half, but shots 2, 3, 4, and 5 would have all made a nice little 100 yd cluster. Same looks true for shots 15, 16 and 17. in which case I would go with shot #16 as the load. Overall it looks like shot 16 in chart 1 is the best load for that combo because POI of shots before and after that sweetspot are less erratic than POIs before and after the low end sweetspot, which indicates a much more stable pressure node..

Chart 2, that rifle really likes that bullet. and it does really well with it at mid range pressures. look at shots 6 thru 12. Thats a 7 shot string that would have all landed well within a 1" group. Thats EXACLY what you are looking for when you shoot a ladder test. The load I would select from chart 2 is shot #9 as its right smack in the middle of the string, and its also the best load from either chart.

Stick with the HDY 55gr SP and 24.9gr Varget. Its money.

[ChuckR]

Thanks to all who answered, Woolly and JLA thanks, for helping me read the tests. I was confused a little in chart A as I did not think you could have 2 sweet spots, but JLA straighten me out, and I also had trouble with chart B, as it did not look as straight forward as chart A. But as JLA explained I can see now how to read this type of test. AS usual, you guys are great at helping us neewbies

Chuck

[JLA]

Next time you do a ladder test do it in .2 gr increments for small rifle cartidges and .3 gr increments for large rifle cartridges.

Save the .1 gr increments for pistol workups. You will have much more readable results that way. But overall you did great and provided another fine example of how to shoot and read a ladder test.

Great work Chuck!