223 chrono tests

[Nude nut]

I have been farting around with my lads 223 feel free to rip this to shreds but I have done this test 5 time over the last week and found some interesting patterns in the numbers.
The loads are from 25.2 of 2208/varget cc I 450s and 80.5 burgers loaded in tenths up to 25.5 gr
Fowler
25.2-2883 fps 25.3-2888 fps 25.4-2920 fps 25.5-2910 fps es-37 fps 10 into the lands.

Test start.
25.2-2881 fps 25.3-2905 fps 25.4-2917 fps 25.5-2920 fps es-39 fps 10 into lands.

5 into the lands.
25.2-2901 fps 25.3-2898 fps 25.4-2913 fps 25.5-2903 fps es- 32 fps

5 off the lands.
25.2-2900 fps 25.3-2886 fps 25.4-2896 fps 25.5-2900 fps es-14 fps

Now I could put up more but I would be here for ages.
Things to NOTE this may get confusing it's obvious that 5 off has lowest e's but look deeper the numbers between the velocities is speed variation between tenths have a look at the pattern changes from left to right with the low numbers as seating depth changes.
Also if you add velocities for each charge from top to bottom you will 25.2 is least effected by seating depth. I'm going to load charges between the velocities with lowest speed variation at there given seating depths and shoot groups at 300mtr when my lab radar turns up so there it is get ripping.

Okay I have removed numbers between each load weight here they are

Foulers 25.2 and 25.3 10 thou in 5fps

Start test 10 thou in
25.4 and 25.5 3fps

25.2 and 25.3 5 though in 3fps

25.4 and 25.5 5 thou off 4fps.

Hope that helps. Cheers Trev.

 

[HomeSlice]

Disclaimer: I’m not an expert

I’m a little confused by the format of your data. As an example, you have this sequence of numbers: 25.2-2900 fps 14. What does the 14 represent?

It appears you’re firing one round per charge weight at a given seating depth, for a total of 16 rounds? I think you’ve got too many variables and not enough data to draw any conclusions.

Please don’t take that as me being harsh, but with sample sizes this small it’s impossible to draw any meaningful statistical conclusions.

 

[Nude nut]

Disclaimer: I’m not an expert

I’m a little confused by the format of your data. As an example, you have this sequence of numbers: 25.2-2900 fps 14. What does the 14 represent?

It appears you’re firing one round per charge weight at a given seating depth, for a total of 16 rounds? I think you’ve got too many variables and not enough data to draw any conclusions.

Please don’t take that as me being harsh, but with sample sizes this small it’s impossible to draw any meaningful statistical conclusions.

The numbers between velocity is fps between tenths of powder I wanted to see variation in speed over the 25.2 to 25.5 weight.
If you look at them inbetween numbers you see 3,3,3 4 fps variation between certain charges and they change from left to right as seating depths changes I know its a bit confusing.
Also if you add those inbetween number from top to bottom you will see 5 off the lands affects es less with 25.2gr.
I did this 5 times over a period of a week or so every time I got very simular results that close its negligible the rifle shoots great with current load was just fooling around then I noticed the left right pattern in between charges with the low numbers that you mention. And for this to repeat its self 5 times tells me that its repeatable the 223 has small accuacy nodes very small and tenths make big changes in the 223.
I am going to load inbetween the charges with the low numbers just out of curiosity we will see what happens soon.

Cheers Trev.

 

[Dusty Stevens]

how does the target look?

 

[JimSC]

too small a sample size to be statistically relevent

 

[boltfluter]

I think your test is beyond the capabilities of any chronograph on the market to date. Sorry to be the bearer of bad news.

Paul

 

[Nude nut]

how does the target look?

I did also shoot the charges and listed seeing depths as groups without magneto speed but not the charges I have chosen.
Basicly what I saw was this the two charges at each given seating depth that had the low fps numbers between them when into the same hole the charge after that dropped out low right by half a centremeter.
I have loaded ammo tonight in between those charges ex 25.4 and 25.5 I loaded between them at 25.44gr would have to cut kernels to get 25.45gr not happening.
I will shoot these at 300 mtrs and use the lab radar when it turns up or borrow my mates so I have loaded in between the speeds with the lowest fps between them at their corresponding seating depths I shall take pics of target and list velocity data may be epic fail but the same patten pops up all the way up to 25.8gr.

Cheers Trev

 

[Nude nut]

I think your test is beyond the capabilities of any chronograph on the market to date. Sorry to be the bearer of bad news.

Paul

Lol I'm still going to see the crony might not but if there all in one hole on the target and hold good vertical out long who cares just having fun you wait until your retired boss you may just waste your time now and then he he.

Cheers Trev

 

[Nude nut]

too small a sample size to be statistically relevent

My wife says that as well.

Cheers Trev.

 

[CharlieNC]

Are the numbers you reported the average of the 5 shots?

 

[Nude nut]

Are the numbers you reported the average of the 5 shots?

No just single shots ex 25.2 25.3 25.4 25.5 one after the other to see e's between 25.2 to 25.5 repeated at each seating depth listed then repeated this 5 times but all them numbers are not posted as the variation in numbers are so close at each test their negligible and at each seating depth it seems that the charges with the least fps between them swap from the low side of the charges then the next seating depth the low numbers goto the higher end if you had a texta worked out the low numbers I'm talking about and joined the dots you will see the patten.

Cheers Trevor.

 

[Nude nut]

Over the five tests there was approx 100 rounds that's not including the test for 25.5 to 25.8

Cheers Trev

 

[CharlieNC]

It sounds like you may have enough data to "prove" your point that the longer jump reduced the effect of charge on velocity. A similar post a few months ago showed similar results on the target. Did your target reflect this as well?

 

[Nude nut]

It sounds like you may have enough data to "prove" your point that the longer jump reduced the effect of charge on velocity. A similar post a few months ago showed similar results on the target. Did your target reflect this as well?

Actually when I went with the longer jump to ten off the es over the same charge weights were over 100 fps so did not go further off.
I'm actually trying to work up to get more velocity but retain good consistent accuracy It's brilliant out to about 700yrds at current load would like to improve the 800 and 900 accuracy.
Not fussed if I can't I have other tools for that job but it may help my young lad a bit he shoots my 308s but has trouble controlling recoil at the present.

Cheers Trev.

 

[Nude nut]

Gray guys,
Well I didn't get the results I was looking for straight up but I did focus on a load chosen from my tests but kept getting the odd flier but I'm sure I solved the problem.
I shot this last test group yesterday morning as we have a open comp this weekend I tweaked the neck tension it is an 8 shot group at 300mtrs the mirage was shocking dewy morning temp 30 degrees C.
Shot of joypod and rear bag velocity was 2965 fps es was 11 it wasn't that low until I tightened up the neck tension using a smaller mandrel and went from 40 to 39 setting with the AMP.


Cheers Trev.