Garmin Xero and Primer Sorting

[Rocketvapor]

Here's the individual weights I could come up with.
Went through two additional flats and didn't find a real heavy one.
I might toss in another 3.755 into row one just to have 5.
See later post (#41) for all weights and shot order.

 

[RegionRat]

Just the nature of the manufacturing method.

If you try to imagine those pasty wet "pellets" of primer compound being squeezed out of the tooling and shoved into the primer cups, it is almost not possible to go "overweight" but easier to get the "lighter" ends of the tail of the distribution.

It will generally look like a reverse gust function that tails off in the light direction, with the only question being how tight the Kurtosis and Skew looks due to workmanship.

It looks something like this.

 

[Rocketvapor]

Actually looks like a LIGHT bias/skew with the CCI450 I have.
Flats average about 3.66grains.
I'm particularly interested in keeping the Outliers Out of the serious shooting sessions.

Question:
How do I get the ShotMarker display to show the whole group?
Sometimes it's set up for me and only shows current/last shot.

 

[RegionRat]

Question:
How do I get the ShotMarker display to show the whole group?
Sometimes it's set up for me and only shows current/last shot.

I'll have to turn mine on and see if I can re-create that issue. I'll try that and come back.

Are you running the current version software or some Beta Test version?

 

[Rocketvapor]

???
It's the range owner's equipment.
He might be there Thursday but sometimes he just sets it up in advance with an IPAD for us to use.
I connect with my Android phone and take screen shots.

 

[RegionRat]

It takes only a few seconds to fix this, so ask him to allow you to click a few buttons.

Step one.

Step two.


After you select "all" shots, you then click on the green check mark and you are running.

 

[Rocketvapor]

Man, thanks a lot.
Not a problem getting into the menu. Happens sometimes with an errant swipe on the phone.

Loading area has been at 51%, 72F most of the evening.
Getting some charging done.
Wife has been dry firing her Savage with the lighter trigger (7.2oz),
Going to try both WIN41 and CCI450 to make sure she has adequate impact for the 41's.

 

[JFrank]

During my hillbilly research I read somewhere CCI listing thier primer weight in Grams which is the same mode i sort them as I see less scale drift and it just seems simpler to keep straight in my little brain.
i sort them in batches .001 on each side of my target number which translates to about 2 kernels of powder.
The question is ~ does that difference in primer weight have a similar effect on the target as powder ?
Anyway…
CCI 450’s listed at .239
.238-.240 as mid and majority
.235-.237 light
.241-.243 heavy
BR-4 majority are closer to .243
Circling back to seeing any change in point of impact at 500 yards during testing? I haven’t been able to yet, however I will continue to sort them for 1 k BR shooting.

Thx for testing and posting your work .

 

[Rocketvapor]

OK, all ready to go tomorrow.
Open to suggestions on shooting order.
We normally take turns shooting, 10 or 20 rounds then swap.
Will be using the Shotmarker and Garmin.
Was thinking taking the fouler shots then 5 Normal, 5 Heaviest, 5 Lightest (for max indication).
Break, let the wife shoot.
Then the next Heaviest, next Lightest.
Break, let the wife shoot.
Finish with the last Heavy, last Light then the last 5 Normal. My thinking this will minimize barrel and environmental inputs, but still not be too complicated to keep track of individual shots.
Thoughts?

Primer weights and shot order in post #41.

 

[JFrank]

OK, all ready to go tomorrow.
Open to suggestions on shooting order.
We normally take turns shooting, 10 or 20 rounds then swap.
Will be using the Shotmarker and Garmin.
Was thinking taking the fouler shots then 5 Normal, 5 Heaviest, 5 Lightest (for max indication).
Break, let the wife shoot.
Then the next Heaviest, next Lightest.
Break, let the wife shoot.
Finish with the last Heavy, last Light then the last 5 Normal. My thinking this will minimize barrel and environmental inputs, but still not be too complicated to keep track of individual shots.
Thoughts?
View attachment 1537844

Use a paper target and different color sharpie on the ogives of the different weights and then shoot them in any order.

 

[Rocketvapor]

I've found that dark colored sharpies hit lower than light colored ones.
( )
I can (hopefully) keep track with the ShotMarker.
30 differences colors?
What I was asking is what order to bring out the differences but not bias from temperature as the day progresses or the barrel fouls. 44 rounds ain't a bunch to shoot in an hour or so.
The last test I did 5 and 5 round robin.

If all goes well, and I don't get confused, I'll have 10 middle, 15 heavy, 15 light individual muzzle velocities, 600yd velocities, and POI of each shot.
(now that I know how to show All shots on the ShotMarker)

 

[JFrank]

30 different colors ?
Any chance you are making this a bit more complicated than needed ?

 

[One Eye Pete]

I shoot F-open club matches alternating at 600 and 800 yards once each a month. I have been weight sorting CCI BR-2s since last August. I don’t get into velocity statistics but what I have noticed is an absence of vertical flyers. On windy days I can still get blown into the 9 ring but my waterline has definitely improved.

 

[rwj]

Best wishes to all in their endeavors! But I have to ask if those sorting primers have ever established if the weight variation solely lies in the ignition compound? If yes, how was it determined?

 

[Rocketvapor]

Pete,
What cartridge?

Never,
has to be some variation in the cup/anvil. Nothing is perfect.

 

[RegionRat]

If your rig has a shot count limit, or a trend within a 20 shot string, then you will want to round robin the shots. If your rig can be trusted to run each sample family in series, then the data is easy to sort when it is all over using the system's group measurements and a screen shot, (or you can always do the math at home from the CSV file later).

With a match gun, I don't worry about Round Robin testing, but I do watch the shot count and fouling issues.

I can generally evaluate each sample family before moving to the next and get away with it.
It is the extreme opposite with carry guns due to heat and fouling. Those just don't do well with more than 5 to 10 shots without a break, and many won't go more than 80 total rounds without cleaning.

With only three sample families to track, you are about six one way and half dozen the other. If you are careful to shoot Heavy-Light-Normal, H-L-N, H-L-N, etc. over and over, then you can always go back and sort those with the CSV file and plot the X-Y position of the shots in Excel.

Another way is to just use the screen and temporarily "turn off" every third shot and the ShotMarker will show one family at a time so you can let the system run the group stats. Then you take turns turning on the next family and repeat for the three families.

One way you get to take the data home and run it all through Excel, the other way you can let ShotMarker do the math on each group and then take screen shots. You can even to both.

I am spoiled in that I have had a ShotMarker since his first ones. I can wait till I get home and turn the laptop screen on and capture screen shots that I then paste into the Excel file. I grew up in the defense business and understood the value of the eTargets before they were available to consumers, so I jumped when I heard about ShotMarker.

Without a ShotMarker, I could never have made personal progress with XTC since catching days off when friends were available for turns in the pits was too rare. Getting 600 yard practice was nearly impossible on your own and the ShotMarker really unlocked that challenge. No more colored markers, no more remote cameras, no more asking the wife to pull pits.... worth every penny.

Good Luck and in for the range report.

 

[Rocketvapor]

thanks, forgot about the 20 round limit.
Limits, always limits
Not going to start and stop something I'm not really familiar with.
If nothing else I'll pencil and paper everything so I don't lose data. BTDT.
SOoo, Here's the way it's going to be (that's my story and I'm sticking to it )
5 shots of the heaviest 5 shots of the Lightest, screen shot. Best chance to show a different.
Start new session.
5 Heavy, 5 Medium, 5 light, screen shot, new session.
5 LIGHT, 5 Medium, 5 HEAVY, screen shot, end session.

I'll stick the wife's 2 20 shot sessions in between mine.
I'll post a comma delimited text file of weights, velocities, and screen shots of targets.

Primer weights and shot order in post #41.

 

[One Eye Pete]

Pete,
What cartridge?

Never,
has to be some variation in the cup/anvil. Nothing is perfect.

284 Shehane

 

[Bronsin]

Best wishes to all in their endeavors! But I have to ask if those sorting primers have ever established if the weight variation solely lies in the ignition compound? If yes, how was it determined?

Would weighing them after firing work?

 

[tom]

Screen shot from Shot Marker.
Seems to be a bit more than 2" with the 22N and 85.5s

Odd # shots were light primers, even number shots were heavy primers.
From Garmin
Shot 10 Heavy 3015.7 was the highest in elevation but wasn't the fastest.
Probably the shooter, not the Primer.
Shot #2 was faster, 3039.3.
View attachment 1533046

Shot round robin, this is all the data you need. The velocities are what they are, and we see higher ES shoot smaller than lower ES even at 1,000 beyond half the time. Good job.

Tom