I haven't figured out how to put a pic on here, so bear with me while I explain results.
270 win, RL-19, 140 sst, 325 yards, 55 degrees
Charges: 1-17= 52.6 - 57.4 in .3 increments.
Started with three foulers and one sighter.
shot 1 & 2 same elevation, 3 inches wide
3,4,5 same elevation (up 2 inches from 2), 7/8" group!
6, up two inches from 5
7&8 same elevation, up two inches, 3 inches wide
9 up 1.5"
10 up 1"
11 up 1"
12 up 3/4"
13 down 1.5"
14 up 2.75", left 2"
15 down 1.75"
16 up 1.25"
17 up 2,5"
14's kind of the wild card.
I know this is not much to go on. I'd like to hear what you think anyways. If this was all the info you had, which charge would you use?
Where would you test next? A ladder using groups for poi, test between 3,4,5, test between 13-16?
Grit, if you can email me a pic, ill post it for you. Looking at the target will tell the tell very quickly. Not having a chrony is a detriment, but you will still a lot of info to go on. Lets see if we can find the nodes, then you will need to load a few more with a charge weight in the middle of them... then play with seating depth if you like.
I sent a drawing first, as I had to install my camera software. I got the software installed, and just sent the pic. If I didn't shave, I could grow a beard in the time it takes my conmputer to upload a picture!
On initial impression, id load a few rounds with the charge wt used on #4, and a few between #11 and #16, banking on the idea that perhaps something strange was at work with #14. Id load a few at #12, and some at #15.
Having a chronograph would make it an easier process for sure, but it can be done without.
Id pick your loads to test, and load 6 rounds of each, then shoot at a pair of targets. After shooting, look at them individually, then stacked, so you have a pair of 3 shot targets, and a 6 shot target to look at. With the load that performs best of those, load 9, and repeat. You end with 3, 3shot groups, 2, 6 shot groups, and a 9 shot group to analyze the load with, while putting very few rounds downrange. Naturally, 3 shot groups will be smallest, with 6 usually bigger, and 9 the biggest, but if your 9 shot group is round, and small, you will be pretty happy with it.
Thanks for your help! What range would you do the accuracy testing at?
I think I managed to pull 14. I'm guessing further, it should've hit next to 12. This gives about 1.75" for shots 11-15. What's with the waves?
I don't think I mentioned in initial post, there was a light, gusty breeze blowing from about two o clock. This breeze died out around shot 10. I didn't expect a vertical string, but I think the wind is responsible for a lot of the horizontal displacement.
I'll test the loads tomorrow. This is fun. I've been trying to decide which rifle to buy next. After today, I know; a new spotting scope.
Abinok how have you been? I am still a student of this ladder test but I am looking at this and thinking his low node is load #4 which is almost dead center between 2-3 and 6-5. And the high node is a load right between 13 and 14. I roughly plotted the shots on a peak style graph and that load would rest squarely in the center of an up and down series of impacts that are a mirror image of each other as follows:
The up and down movements are remarkably similar in size with 10,11,12 being a bit shorter than 17,16,15. Looks like a growth and decay of an obvious harmonic occurance. Viewed like this makes 14 look alot less strange.(totally ignoring windage though)
But I'm still new at this. If you disagree please give some detail as to why so I can get this figured out.
Upon reviewing the picture again it seems that a load between 7 and 8 may hit another, more sensitive node centered between 6,7 and 9,8
GRAVITY. It's not just a good idea. It's the LAW!