The answer to my 223 ES pissing and moaning?

So my Bergara 223 is shooting okay ish, getting very close to being MOA for 10 shots. However the ES is still all over the place, 70 to 130 is not uncommon with the same load - 73gn ELDMs with 23.5 of H2206H, in Sako cases (I changed from Lapua in desperation) with Rem 7.5 primers (I also changed from Fed 105s).

I've tried a lot of things both load wize and with rifle mechanics.

Tonight I tried an analytical approach . . . . I put all targets I've shot with the rifle in date order and reviewed them. Nothing spectacular jumps out but I'm wondering if this target tells the tale? It's a seating depth test. Shot at 100M

Attachment 251575

There is a lot of data on the target (not enough to be statistically valid! but beggars can't be chosers sorry @gimp ) but I'm looking at the average velocity, from seated about 10 thou off lands to factory length the average velocity changes by 86 fps, dammed close to what often happens with a 10 shot group.

Any thoughts of "is it related to the problem" and potential solutions?

Thanks
Foster

Have you tried grabbing a random sample of five or six different types of factory loads and trying those for results? Just really to see if the different loads has one type that shines out as 'one hole' groups (and try and reproduce that load if the pill will do what you want) or they all do the same thing in which case for whatever reason the rifle is shooting to it's potential and you either accept it or replace it?

The point I'm making is it might not be anything you're doing, and you seem to be generating a lot of data with fine tuning level changes but all of it seems to me to be very similar and nothing really stands out to me as pointing you to go 'that way, there is your answer'. Changing the seating depth might have resulted in some identifiable velocity figure differences, but your targets tell the story to me. Mean point of impact for each group looks virtually identical from my eyeball assessment?

Have you considered something left field like crimping a few reloads and seeing what the results of that is, noting that a lot of subsonic reload users have found that velocity and accuracy can be a little variable with uncrimped reloads? Or another option - returning to safe level start loads for a few and leaving the pills long to jam in the leade so you take any possible variation in bullet release in the case out of the loop?

I see what you are finding there, other people with .223 load up using a fork and a teaspoon from the cutlery draw and get one hole groups whereas for whatever reason you find 1MOA and that's all she's got. I have had similar things happen in the past, I'm told they call it character building.

I've found my results have improve since I started using a sonic cleaner.

So you tried a lot of things load and rifle wise

What about cases
Particularly case neck tension. Inside reaming and outside turning ?

And I like the sonic cleaner idea

I had case neck tension problems with my Bertram 222R brass. Inside reaming was the answer

Quote:

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Originally Posted by 7mmwsm

I've found my results have improve since I started using a sonic cleaner.

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Ties in with the subsonic people's findings - a lot of their issues stemmed from variance in bullet release. Seems that sometimes the primer was enough to eject the projectile, other times it needed the powder burn as well. It might be a possible solution - Lee crimp die $29 + shipping from Reloaders? Picked one up in .308 when I was in Aucks last for sub ammo.

Have you tried sorting projectiles base to ogive? I've found the batch of 73's I am loading have quite a few thou of variance. Luckily in my case I am getting acceptable SD for my application.

24.5gr 2206h
PMC once fired brass
S&B SRP
About 3 thou neck tension and seated 1.821 CBTO (more or less 2.26" OAL)

Over 20 shots, on different days the aggragated velocities were 14fps SD if I recall.

I got 12fps SD today validating data at 288m, over 12 shots, everyone hitting centered on a 6" plate. Can't be bothered trying to get better than that.

I'm running into the same issues as you with inconsistent velocity (up to 30sd and 110fps ES) in my 6mmCM. All loaded to very tight tolerance with two different powders, 3 primer types and two different bullets, peterson brass that had good velocity trends on first firing (which tells me it is probably something I've done to the brass), amp annealer, checked for firing pin drag, cleaned the barrel to a spotless.
I'll try a different neck tension technique and then new brass next.
Groupings are great at 100m and only abit more vertical from 300m+
It's bloody frustrating ay!

Whats your rifle? Im sure that my Bergara has at least a wee bit of ignition inconsistency contributing to my issues.

Tikka action, trueflite barrel.

Greetings,
To me the load looks a bit light. Granted the Sako cases are heavy and you may be running into compression issues but I would try upping the charge a little. Many rifles shoot best when close to max.
GPM.

Greetings again,
It crossed my mind that you may be concerned with the heavy Sako cases running the pressure up. I looked at the Hodgdon data for the 75 grain JLK VKD projectile and I am guessing that you are running a 22 inch barrel or close to that. This would mean that your velocity lines up pretty well with predicted so you need not worry about pressure. An additional grain of powder would give around an extra 100 fps. These loads are held to lower pressure for the Semi Auto's so there is a bit of a margin when working with strong bolt actions. In my younger days some pretty hot loads were listed for the .223 which I used without problems often with AR2206 (not the H version).
Regards Grandpamac.

Haha 18" so it's not a light load, I changed back to Fed 205s and the 10 shot average of today's group was 2774 fps with the 73s (from 23.5 of 2206H). Full report upcoming after dinner.

Been a long dinner break, hope you haven't made a meal of it.
Na I'm just chucking cheap & cheerful hornady 55 spcbt, BM2 & rem 7.5 primers & they are grouping half inch at worst, no real idea of speeds or es only wacking paper at 100, need to purchase a chrony, then all turn to :wtfsmilie:

Quote:

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Originally Posted by flock

Been a long dinner break, hope you haven't made a meal of it.
Na I'm just chucking cheap & cheerful hornady 55 spcbt, BM2 & rem 7.5 primers & they are grouping half inch at worst, no real idea of speeds or es only wacking paper at 100, need to purchase a chrony, then all turn to :wtfsmilie:

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What did I say about people loading with a fork and spoon haha

what have I often said about chronicgraph ruining a perfectly good load....