brainstorm with this data

[DUSTY NOGGIN]

range day went .... undecided

awesome sd's , not so good accuracy

1 1 68.70 2990
2 1 68.70 2976
3 1 68.70 2990
4 1 68.70 2983 SD 6.70 - group size 1-1/2 ** could a been me getting settled **
1 2 68.80 2994
2 2 68.80 2972
3 2 68.80 2976
4 2 68.80 2979 SD 9.60 - group size 3/8 all touching
1 3 68.90 2998
2 3 68.90 2974
3 3 68.90 2982
4 3 68.90 2976 SD 10.88 - group size 1"
1 4 69.00 2992
2 4 69.00 3005
3 4 69.00 3003
4 4 69.00 2996 SD 6.06 - group size 1-1/8"
1 5 69.10 3005
2 5 69.10 3005
3 5 69.10 3013
4 5 69.10 2996 SD 6.95 - group size 1-1/2
1 6 69.20 3001
2 6 69.20 2990
3 6 69.20 2980
4 6 69.20 2994 SD 8.77 - group size 7/8"

 

[RockZ]

Try a seating depth test at 69.1

 

[Canhunter35]

I'm curious how accurate is your scale to be adjusting by .1 gr. It shouldn't make really that much difference?
I agree that the 69.1 is most promising in terms of es

 

[DUSTY NOGGIN]

I'm curious how accurate is your scale to be adjusting by .1 gr. It shouldn't make really that much difference?
I agree that the 69.1 is most promising in terms of es

i think i got the scale down fairly well - it is electric ... and takes a steady temp to see a span without any swings -- i always check 3 points of measure 1. when pan is offit equals -112.2 after scale tared with pan on 2. 771.6 grains with the 50 gram check weight 3. i trickle until it just barely goes to target weight , if i see 2 drop in , ill scoop three granules out ( and work my way back up til 1 granule makes scale move to target weight -- while constantly lifting to see what the negative tare weight is , if all 3 dont line up it doesnt go in the case - im sure there is variations still but i feel i have done everything to get as close as possible with an electric scale

what i am tripping on is that 4 shot group , with no sign of variation 0.1 grain either direction , if it wasnt for the low numbers , i would have looked at the lower speed platuea in the 66.0 68.0 range --

here is the full power OCW chart - retumbo @ 64.5 through 70.5 no pressure

 

[Canhunter35]

3k and 2825 look like your velocity node for es, but perhaps improved case prep will further improve it.
Do a seating depth ladder test and determine best depth and you should be on your way

 

[RockZ]

Great job plotting. Gives a great picture of what's going on.
You guys nailed it. Just do a seating depth test for the loads in the middle of the flat spot of the graph. Looks like loads 5 and 10.

 

[DUSTY NOGGIN]

3k and 2825 look like your velocity node for es, but perhaps improved case prep will further improve it.
Do a seating depth ladder test and determine best depth and you should be on your way

i will mess with seating , before i move away from #10 load area , i at least had to see if the higher velocity would work out first

so as far as case prep go ,i went very extensive with these, all have been sorted from a huge lot started with 200 or so ( down to 60 after sorts ) ,
all same headstamp RP
neck turned , sorted by anything with more than 1/4 not touched by turner , didnt make the cut (( pun intended ))
*** all above data this is there first firing since turning ***
uniformed primer pockets , sorted by any that didnt make a complete new surface --
deburred inside primer hole trimmed all to match (this made case weight among the whole group a lot more consistent)
sorted all cases by weight
also did a sort of longer than my once fired case base to shoulder length before sizing anything
Sized cases to match .002 less than rifle once fired ,
trimmed all cases , cases that did not contact cutter were sorted out
redding comp dies and +.010 comp shell holder

all annealed with tempilac , had alot of sorted brass to use for annealing timing test

shot count is at 46
have 20 prepped of first batch left for seating test, so i can probably do 5 sets of 4 , or 4 sets of 5 -
i can only go a little longer- i think im .020 off now , gotta check notes

i would like to shoot all remaing 20 for seating test - to get the turned neck centered

 

[Canhunter35]

i will mess with seating , before i move away from #10 load area , i at least had to see if the higher velocity would work out first

so as far as case prep go ,i went very extensive with these, all have been sorted from a huge lot started with 200 or so ( down to 60 after sorts ) ,
all same headstamp RP
neck turned , sorted by anything with more than 1/4 not touched by turner , didnt make the cut (( pun intended ))
*** all above data this is there first firing since turning ***
uniformed primer pockets , sorted by any that didnt make a complete new surface --
deburred inside primer hole trimmed all to match (this made case weight among the whole group a lot more consistent)
sorted all cases by weight
also did a sort of longer than my once fired case base to shoulder length before sizing anything
Sized cases to match .002 less than rifle once fired ,
trimmed all cases , cases that did not contact cutter were sorted out
redding comp dies and +.010 comp shell holder

all annealed with tempilac , had alot of sorted brass to use for annealing timing test

shot count is at 46
have 20 prepped of first batch left for seating test, so i can probably do 5 sets of 4 , or 4 sets of 5 -
i can only go a little longer- i think im .020 off now , gotta check notes

i would like to shoot all remaing 20 for seating test - to get the turned neck centered

Never mind my comment about case prep lol.
What type of chrony?

 

[dok7mm]

A couple of possibles - @ 46 Rd count, the barrel hasn't settled in. Or, difference in neck tension, as brass, even annealed, can show different springback. Uneven barrel temperature in shot string. Seating depth has been mentioned. Finally, weight sorting is not a true way to sort case capacity.

Your rifle may hate your bullet or primer, but most likely it's the seating depth. Did you check run out?

 

[DUSTY NOGGIN]

A couple of possibles - @ 46 Rd count, the barrel hasn't settled in. Or, difference in neck tension, as brass, even annealed, can show different springback. Uneven barrel temperature in shot string. Seating depth has been mentioned. Finally, weight sorting is not a true way to sort case capacity.

Your rifle may hate your bullet or primer, but most likely it's the seating depth. Did you check run out?

its a MS V3 chronograph. which seems to read everything really good. i put a little sharpie dot on barrel since recoil pushes it forward about 1/16 to an 1/8 every firing. on this latch batch i readjusted every shot to even the strap to the sharpie dot

barrel is a pretty heavy contour which they called an S7 varment 1.060 to .800 @ 28" , SS select match .. i didnt think there would be this much movement

cleaning/break-in procedure , every shot for 4 , every other for 6 , it cleaned very easy so i stopped there. It took 4 about hours to shoot those first 10

as far as feel in seating bullet force on press. they all felt very very even quite soft compared to others that i have done. i aimed for .002 tension which and i do have one smaller bushing to try if needed, used the vld seater stem in comp seater which did seat concentric max was .004 average was .002 on OCW batch i assumed it would be fairly close to those. So , no i did not check concentricity on this batch, i do have the 20 first prepped left. so once those are seated ( seater is still locked in the press ) i should be able to get an idea of this batch

i am not very good with water/capacity testing, but i will try it again , what variation do you allow for to be considered sorted out

should i do a copper cleaning pass again ,

 

[curtiscd]

I'm with the others that are suggesting a seating depth test. Given all your numbers we are talking an SD of 11.48 across 24 shots in a .5 gr range. This isn't perfect, but realistically it's pretty solid. Once you find optimal seating depth I think you'll be very satisfied if you settle anywhere in the middle of this flat node. Given that the 24 shot avg is 2990 with a pretty good SD I'd settle in around 69.0 gr and see what happens.

Good Luck

 

[DUSTY NOGGIN]

id take your recommendations for seating test for this next step
checked notes and max touching CBTO=2.669
all of the above shots seated to CBTO=2.654 so .015 off

how much shorter do you think i should go ?? .090 ???

how many times would you split that .090

 

[DUSTY NOGGIN]

would you clean it to steel , or leave it dirty for this test

 

[Canhunter35]

Clean it for the new ladder test.
I'd test in .02" increments. Then once you identify a node, test at .005" with another small ladder test around the identified seating depth and you should have it pretty much ready to go