Load Analysis, Your assistance would be greatly appreciated

[birdiemc]

I know I have to start annealing, yesterday I was trying to work up a load and had a neck split wide open on my second to last round, then went back and looked over the rest with a flashlight and found 2 more with hairline cracks.
1.Do the split necks screw up the velocity data I gathered?
Rifle, 308win, 20" barrel suppressed, remington 700 in magpul hunter stock.
Shooting 168smk, Varget 42.0-46.0 in .4 gr increments.
Brass prep, twice fired federal brass. Not tumbled. Using lee press and dies. FL sizing die bumped shoulder back .002. Measured all with comparator, all exactly equal. Did not trim or measure this firing, previous firing trimmed to 2.007 (nothing magical about that number just didnt want to screw up and overshoot trying to get to 2.005) lee delux case trimmer. Cleaned primer pockets, seated primers with lee handheld, primers vary from .001-.006 below base of case. Seated bullets as long as they will fit into my magazine, avg COAL 2.885, CBTO varied only .001 (as good as I could get with equipment I have). Did not sort bullets or cases by weight. Using lee beam scale. Tediously measured powder trying to get the exact perfect charge. Triple checked my numbers before filling the case, then checked again before moving on to the next charge.

2385, 2377, 2478, 2422, 2469, 2495, 2526, 2521, 2545, 2552, 2591, 2601
Checked over magnestospeed.

2. Based on everything I've said so far and the velocities I recorded, is this worth even looking at, or do I have too many things working against me to make any sense of this?
I will say when looking at this on a spreadsheet I noticed loads 7,8,9,10 only have a 31fps spread, which is what many have one to the next so was thinking about picking the middle there and loading up and down .2 gr in .1 gr increment and see what I get. What would any of you do if you were in my shoes?

I do intend to get a flsh hole deburring tool either sinclair or k&m, as well as primer pocket uniformer.
I bought a cheap hornady digi scale today so I can start sorting brass and bullets, the thought of doing that on that lee beam scale, well it kept me from doing it. I have started keeping track of brass, labeled in zip lock bags by headstamp and number firings. Trying to go in the right direction just cant afford to buy everything all at once.

Edited to add rifle info
Edited again to put correct starting charge weight, accidentally typed 44gr when it was actually 42 gr

 

[Lefty7mmstw]

First, ditch the fed brass is you don't want cracked necks (possibly good throwaway brass for hunting, etc.). I've seen fed 338 brass crack just sitting on my shelf loaded. Second, a 308 won't show that big of a change on .4 grain increments. It can be run in 1 grain steps until you get close to high pressure then tweaked in small increments after that.
With the 223, 270, 30-06 and the like I often do not bother to find the top speed as they will shoot just fine a few fps down; as long as I have decent accuracy I am happy. I have bigger hammers in my toolbox if I really need to hit something hard.

 

[birdiemc]

Shouldn't annealing help with cracked necks?
And any recommendations regarding the data I posted?

 

[BallisticsGuy]

Inconsistent neck tension will affect your Velocities but not probably by much. Your SD's will climb and group size will probably suffer to points that, for me, would be an unacceptable level (match shooting). When I filtered your source data using a kinda an admittedly ad-hoc filter but a filter nonetheless, you get a pretty smooth trend line forming. I'm going to bet that you're very near a max load at 46gn if you're not already seeing flat primers.

Annealing will help but so too might looking at how much you're resizing your brass. That's the ultimate cause of split necks, working the brass hardens it. So, take some careful measurements of OD before and after firing and after sizing (before seating a bullet) and after seating a bullet. We can look at that and be able to tell you more.

 

[DUSTY NOGGIN]

Shooting 168smk, Varget 44.0-46.0 in .4 gr increments.

2385, 2377, 2478, 2422, 2469, 2495, 2526, 2521, 2545, 2552, 2591, 2601

you need a new batch of brass , once fired

 

[DUSTY NOGGIN]

i have some annealed brass, that i could send you

but to keep this LD going id load 10 or so at (( changed )) , and record speeds

 

[SealT5]

It's a brass issue. Get some lapua or one of the new USA flavors

 

[birdiemc]

Ballisticguy
I will check some brass as soon as I get a chance to see what I'm getting before sizing, after sizing, and after seating bullet.

Dusty
I shot one at each charge weight so each velocity represents one weight, increased .4 gr from the next, starting at 42 gr. Can't figure out how to insert the chart from excel so hopefully screenshot inserted below works.

 

[birdiemc]

Just a note, I loaded up 3 rounds at 42gr, but only included the 3rd fired in my original posting because the shoulder was bumped .005 more on the first 2. Whereas all the others were identical.

 

[birdiemc]

I have some once fired federal (factory match kings) that I can load up and try shooting. Perhaps 10 at 44.6 and 10 at 45.4...

 

[Canhunter35]

Umm, how did the shots group on paper?
What I would do is leave the chrony off the barrel, and load up in .5gr increments starting at 43-46 and shoot 400yards or farther on a calm day, your grouping and vertical spread will come together and that's your node. Then you can do the same thing with a seating depth test if you're still not happy with results
I would be surprised if your gun doesn't like near 44gr of varget with those 168s

 

[DUSTY NOGGIN]

I shot one at each charge weight so each velocity represents one weight, increased .4 gr from the next, starting at 42 gr. Can't figure out how to insert the chart from excel so hopefully screenshot inserted below works.

so i edited , my original post ,

after you pick "upload a file" then pick the file , it will show the files you are attaching to your post & will give the options of thumbnail, full image or delete .. pick full image

i think that little valley in your chart @ 44.8 is a good place to test around with the same federal brass you used,
im betting 45.0 will be your rifles number with that brass --

if you have annealed the FC brass that didn't have cracks , i think you could save them to complete this LD , or find some more FC and anneal em to continue

when making spread sheet charts a forum member a few months back did something that i think gives a better visual idea of what going on ,, and that was basically running 2 series at the same time

2 @44.4, 2 @44.6, 2 @44.8, 2 @45.0 ,2 @45.2, 2 @45.4, and 2 @45.6
so that you have 2 (or 3) series lines running next to each other , that seems to really show when the SD tightens up , 3 would even be better IMO

 

[birdiemc]

Umm, how did the shots group on paper?
What I would do is leave the chrony off the barrel, and load up in .5gr increments starting at 43-46 and shoot 400yards or farther on a calm day, your grouping and vertical spread will come together and that's your node. Then you can do the same thing with a seating depth test if you're still not happy with results
I would be surprised if your gun doesn't like near 44gr of varget with those 168s

Honestly I was just shooting for velocities, wind was terrible that day. I didnt even walk down and look at my target. I can shoot 100 yards out the back door of my shop so I'm trying to do all my load development at that distance. It's a couple hours drive for me to get a 400 yard shot. Only range I know of around here with more than 100 is only 300 and steel plates, so not ideal

 

[birdiemc]

Dusty, I ordered some stuff from brownells just waiting for it to get here, then going to do exactly what you suggested. Got a primer pocket uniformer and flash hole deburring tool coming. Figure if I'm gonna do it I might as well do it right. I even been eyeballing my lathe complemplating the best way to use it to turn down necks. And by best way I mean cheapest way with what I got, but still achieve perfect results.