Help me interpret this data! (Picture Heavy)

so in your loading data chart, what brass did they use?? Did you know federal brass is thicker and heavier then winchester brass, and a load that is safe in winchester brass may exhibit pressure signs in federal brass....whereas Lapua brass is thinner and may require more powder to achieve a listed velocity/pressure.

This is why we don't mix headstamps unless we know we are running low enough pressures that what is safe in one is safe in all, it is also the number one reason that what load of powder works flawless in my rifle may not work so well in yours.

Were you using all Federal brass that day? or did you have one sneak in with the others?
 
Before I loaded anything, I documented the brass measurements just for comparison sake when purchasing new batches. I think the technical term is "anal retentive".

I've always sorted brass by headstamp, how many times fired, etc. I'll only clean 50 round batches at a time and those brass never leave that batch, regardless of how many of that specific headstamp I have. If the cases exhibit loose primer pockets while seating, I'll mark the case with a sharpie. I've had 2 dislodge primers in the magazine upon firing. Those brass get turfed and I dont supplement that batch with any others. So of the original 50, if only 48 last through 4 firings, that's all I'll reload.

I wont get into how crazy it drives my OCD.

Because I have 2 rifles in 6.5 Creedmoor. I separate them into what weapon fired them. Despite full length resizing, I keep brass to that specific rifle.

The book is Hornady. I've proofed each headstamp with loads varying from way low to exhibiting pressure signs and documented it all. Each bullet, primer, seating depth combo. It makes it nice for comparisons sake.

I can actually see how the brass measures up between headstamps with muzzle velocities, and at what point pressure signs were reached.
 
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However, as you stated, one of the variables I havent been able to document is at what temperature the barrel is when I commence a string of fire.

Hindsight being 20/20. After seeing how consistent this Lapua brass is, I'm kicking myself for not biting into them in the first place and developing from there.
 
oh, and I forgot.....

lube left on your cases will form a barrier between your brass and the chamber wall, allowing the case to slide back against the bolt face thus usually piercing the primer

so are you a shooter or an engineer?? lol, you've gone way up and beyond what most shooters do, record keeping is awesome for future reference and what seams so trivial today could be your god saving grace tomorrow
 
blue, in this thread, you have shown many times, that your combo of reloading and rifle as showing EVERY type of pressure sign. The pierced primer is just another sign telling you to stop loading at this powder charge level.

Review your past targets and you will see that 39.6gr repeatedly shows excellent accuracy... any thing over 40gr shows all types of pressure signs.

Accuracy trumps speed but if you feel the need to try and get to the higher node, consider a slower powder like H4831SC. Your rifle and brass and primer have done their job to tell you that where you are going is not safe and not accurate

Using a tougher brass is simply going to mask the real problems in your combo and the brass will still fail ... just will take a few more firings.

Jerry
 
bluedixon said:
Rick, eagle eyes!


I had resized, however after your post, I scrutinized my whole setup again. Turns out, I hadn't tightened the lock ring down on the die and it had walked out some.

I full length resized again through the hole batch this morning, and ran a few through the neck turner. It also occurred to me that I'll need more neck bushings, the 4 I have aren't tight enough for 0.002" neck tension on the bullet.





Do you guys steel wool the necks after turning?

Dave, thanks for chiming in too. Your guys experience has been key in my learning process.

The "black" bullets were right in this rifles wheelhouse as far as weight it seems to prefer. Curious to see if it amounts to any velocity difference. I'm sure its negligible at best if any.

Do they resist copper fouling any? Im sure before I start to put these pills down range, I'll want to do a full clean on the barrel.

Im thinking I need a lab coat.
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Looking better now. I don't bother doing anything else to the neck after turning. My next step is neck sizing and loading. You could polish the neck if you want to make really shiny brass and spend the time. Too much effort for no purpose in my books.

One thing to work on is turning to the same neck OD as well, at least for same brand casings. Bottom line is that you want to be able to use the same neck sizing die without chasing around various sizes for different batches. It is one of the reasons I use all the same make of brass all the time. I neck turn everything on either the second (300WM) or usually the third reload (.223, 6.5, .308) once the brass is pretty much all fully fireformed to the chamber fully. And yes, I have noted that it takes a few firings to get it to a comparably similar size across the entire 50 or 100 cases. I don't know about others, but I only neck turn once. All I am looking for is a consistent wall thickness and concentricity and the neck turn gives it. I neck size after that with either Forster or Redding dies right to the junction with the shoulder. If a person isn't neck sizing the entire neck, I can assume that the neck will require further turning at some point as the donut forms. I leave the expander ball in place even though it never touches the inside of the case neck in any effective manner in most circumstances. The expander ball is only there to remove any possible dings in the neck during ejection or landing on concrete after ejection. I have measured each of my expander balls and even the carbide ones are 0.002 to a maximum of 0.0025" under bullet size. The one I had a problem with was my Redding .223 Competition expander ball and when I first installed it, it was always pulling on the way out. It wasn't long before the digital micrometer checked it out and found it was only 0.0015" under the nominal 0.224" bullet size. Some emery cloth and mounting it up on a bolt with a nut tightened down a little to stop it from rotating on the bolt in the drill press soon took care of that.
 
I had a major chainsaw injury a few years back. Was off for almost a year after, I took up machining. Even bought a mill. Really spurred my interest down to thousandths. Not to mention, my mom was a science teacher.

I feel as though I've only scratched the surface, but once you peer underneath, it goes a heck of a long way down.

So glad I have the knowledge here to resource.

Talking about lube left on the case. I ultrasonically clean after I deprime. I've thought about prepping the cases to the full extent and then bathing them again to resolve any residual wax and oils. Especially now with neck turning, wax on the inside, and cutting fluid on the outside leads me to believe this is going to become critical to avoid any contamination.
 
Thanks for the reply, Rick.

I'll be honest, I've removed my expander ball from my Redding dies. I utilize mandrels for any neck imperfections.

On the sizing to the neck junction, if I crank my bushing all the way down, its actually held captive and thus doesnt allow it to concentrically align itself. There is approximately a 0.070" portion of the neck that is not sized by the bushing between it and the finished neck turn cut into the shoulder.
 
For the firings prior to neck turning, I resize the neck only with the Lee neck collet die which squeezes the neck on to a mandrel. Once fully fireformed and neck turned, I use the neck bushings for resizing the neck. The ball is only there to catch the rare neck ding. I could use a mandrel whenever I see a neck ding, but I like being consistent with the neck sizing method I use once the necks have been turned. At any rate, I have gone back through the message list and I have to agree with Jerry, you are pushing things big time. Your best loading is definitely in the 39.5 to 40.0 range with 39.6gr being what I would choose.
 
Still reading the thread, so maybe you've done it already, but a lot of guys are notching the action to clear longer seated bullets for this reason.
I don't know if you're up to date on the memo, but Bergara recommends magnum primer if you're reloading with small rifle primers. They've had some bolt shrouds break on them.

bluedixon said:
Granted, while I was loading, I marked any cartridges that felt as though the primers went in too easy. There was only 2, and this happen to be one. The oddity is that these are only 2x fired. Loose primer pockets already?

Thinking this was simply bound up, I tried cartridge number 2. Wont feed.

2 seconds of looking into the breech, and I realized that I'm a complete moron. The nose of the bullet, extends under the feedramp 0.080".

Instead of single loading these and testing them, I went and pulled my targets and came home. If they wont feed out of my magazine, they aren't any use to me. Now I'm facing seating much deeper with a jump of nearly 0.080-0.100".

I'm that dog running around his leash pole, with it shortening quickly. Lesson learned.

Always do a dummy, and test.
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I completely missed your post there Jerry!

I value your opinion greatly. 39.6 has been my go to since almost my first batch. I think the disconnect was chasing the book max thinking I might be missing out on a node that would carry some more velocity. Especially at nearly 1.5 grains under stated max. 80fps isnt going to break me, and as Dave stated long ago, I have everything to benefit from loading lower.

Tokay, I didnt know about either of those points. Thanks for letting me know!
 
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I would guess that the bore of that barrel is a bit small so pressures are ramping up way quicker then expected.

Always look at the pressure signs... you, literally, have photo documented them all. I give kudos to the Bergara receiver for functioning with pressures this high.... well made.

The next barrel may let you get to 42gr... who knows. Just listen to the rifle in hand and load accordingly...

And Safely.

But I would really test H4831SC... it might be slow enough to get the velocity back without excessive pressure. Start at 40.5gr and work up - keep track of velocity and pressure signs...

Jerry
 
Is it just a witness mark on the case head, or has the brass flowed into the hole of the executor and is now raised up?
If it’s just a witness mark, I wouldn’t consider it a pressure sign. Especially at these powder weights. Heck, I get it in my HMR with factory loads.
Now a raised hump I’d be worried about.
 
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