load testing question now with part 2

hi guys
just a question about what you guys look for in your load testing as I keep hearing different ways to go about it eg look for groups, chose the best ES and SD etc

I used a magnetospeed v3 the other day just to see what my load testing was doing as I have swapped to 2208 and 105gr hybrids in my 6BR, 1st time using a chrono to test my loads
these shots were at 200m in slight breeze from about 45 behind me and with slight mirage, was set to 300m to test but mirage was too bad so brought it in to 200m
are you guys looking for good groups between 2 different charges eg hitting on the same centres or are you using your chrono reading looking for single numbers for ES and SD
and then adjusting your seating depths to bring in groups, then neck tension, primers etc

these were set up with .002 neck tension, .010 off the lands and yes I do believe the magneto speed does affect the groups as its attached to the barrel but I just wanted to get speeds and have a new set or rounds to test with magneto off  
see  pic for same load tested with and with out magneto (Left on Right off)



started to get pressure at 30.8gr slight extractor marks starting



29.6gr
min 2852
max 2864
avg 2858 SD 5.0

29.8gr
min 2863
max 2878
avg 2872 SD 6.8

30gr
min 2879
max2894
avg 2884 SD 6.8

30.2gr
min 2901
max 2917
avg 2905 SD 7.5

30.4gr
min 2913
max 2918
avg 2916 SD 2

30.6gr
min 2936
max 2945
avg 2939 SD 4.1

30.8gr
min 2953
max 2983
avg 2969 SD 12.6


like I said I will be retesting on Friday without the magento speed on there and will post up results

Hi Stuart,
Not sure what any one else thinks but I reckon you had better stop testing..... your 30.6 & 30.8 loads have returned sub .5" groups  at 200 meters and your velocity is over 2940 fps.....your problems are over!  
These loads should easily go sub 1" at 300 and that is about all I ever look for at that range with these types of bullets as sub 1" at 300 means it's theoretically possible to go sub 2" at 500.....if you could shoot all your targets sub 2" at 500 and keep them centred you'd win every match you entered.
The info from your chrony will be valuable to compare different powder lots & bullet lots etc, so keep it all.

Regards,
Belly

I agree with Belly.... I like your 30.4 - 30.6 loads as vertical is very small as well...

Wait for a very still day, set up a flag or two and test 30.4 , 30.6 & 30.8 at 300 ... maybe do 2 5 shot groups with each...

Then pick the best charge, try seating depth (0.012 jammed and 0.025 jumped) see if either is better than the 0.010 jump you are already using.... Again pick the best of those....

Then check out the calendar, drive 3000 kms west, shoot a competition and kick our arses :)

Cheers

Anthony

haha thanks guys very helpful on the way Im going to go
yeah like I said I have made up a few and will test again as I believe the magneto speed was affecting groups but re testing without will be a good comparison for future reference
I also liked 30.4 and 30.6gr, don't think I will worry about 30.8gr as I just started to see pressure signs

as for seating depth I found my gun like the VLDs about .050 jump so I will be testing the hybrids out to that  also from .012 jammed

haha would love to come over and might just do it one day after a bit more practice, only got 2nd on the weekend with 195.1, but I was only 10 behind winner
my best group (8 score) of the day in the 4th round  (oh they were with 105gr berger hunting vlds and 29.5gr of RL15, so hopefully it will be better with the 2208 and hybrids)



as you can see the club doesn't change targets as it saves time and we just score after each round.. only bummer about that is if we get a record (unless its on the 1st round) it wont count

great to see the detail on your load development the best load from the pictures is the 30.8 because of it's vertical dispersion. I shoot 4 shot groups at 300m and ignor 1 shot that is out of the group. also the flatest in vertical is the best group as width wise has no bearing on accuracy if the group is 3 inches wide but 4mm in elevation this is a much better load than one that is 25mm round and in the centre. Rifles don't shoot wide groups this is caused from the conditions so discount this and look for the flatest in vertical.

A magno speed or anything that attaches to the barrel is going to cause you problems because it changes the barrels harmonics. So do the load development then check the speed. Speed is not accuracy it is an indicator of what node you are on either the high pressure accuracy node of the low pressure. Remember pressure is speed and high speed is high pressure and quicker barrel errosion

Another factor to consider is try and identify parameters when you are doing your load development such as temperature and humidity as both of these have a much greater effect on load deveopment than anything else.

I like to do my load development in the afternoons as i have found that doing them in the morning when the air density is greater causes more inconsistencies.

just my two cents worth

thanks for your input Les :)
yeah the problem with Perth is usually the best time to load test is the morning as the wind always seems to pick up in the arvo.. bloody sea breeze haha. and my problem is of time as I work away I usually have so much to do when home (I will blame the wife for that one haha)
yeah my quick test on the having the magento speed on/off  was interesting , that 29.8gr test was vertical with it on but off it went horizontal, so that's why I'm going to re shoot the loads that showed promise and go from there

least I have a good lot of data now to check loads against later, I will re test on Friday and post up my results

thanks for all your input guys, great help as I have been trying to use the OCW before but finding it wasn't really doing it for me
cheers
pethy

ok guys got down to the range again and tested from 29.8gr up again at 300m this time
and looks like from 30.3gr up tp 30.6gr is where it was


going to start seating depth
should i stay with 30.6gr or choose say 30.4gr as the vertical .1gr either side good (for temp and if scales are a grain under/over) and then play with seating ?

cheers
pethy

dont know whats up with my target calculator ?? 1st group measures 1.777" center to center
about 1.023 center to center for 30.4gr
about 1.141 for 30.5gr
.669 for 30.6gr center to center
but you get the idea for height

Hi Mate,

Can't see the lower powder charges to compare..... but that is 4 groups all under 1" at 300 .... Don't fiddle too much !!

30.3 looks good to me as there is virtually no vertical.... as long as 30.1 or whatever you tested below that was ok.... I would stay there, if not so good below... come up a fraction to the 30.4 or 30.5.... but honestly all of them are pretty good.

Cheers

Anthony

nah haven't included the lower ones as they weren't the best .30.2gr opened up, lots of vertical
this lot was the best
yeah the target calculator is playing funny buggers as i manually measures from center to center  for those groups and got these
 30.3gr group measures 1.777" center to center, but if you get rid of that wide one its only just under an inch
about 1.023 center to center for 30.4gr
about 1.141 for 30.5gr
.669 for 30.6gr center to center

yeah what to do haha, i wish i tested 30.7gr now haha