Lapua Brass

[Ghansen]

I was referring distinctly to the copper/tin content conferred by the analysis in the article. There is a very large difference, not just a minor inconsistency. A 20% increase in copper is a very major change. Different girls altogether I would have thought.

Nb. As a core component for manufacturing a product, many products with that degree of variation are not likely to pass quality control, so rather I would believe Lapua knew the new ratios and for whatever reason a management decision was decided to go with that. It would either be for cost or benefit to the final product. Not a mind reader or into watergate so thats just my take.

 

[AndyTaber]

What the article represents is a snapshot in time for the particular manufacturers. There is no reference to what the sample size was. Most likely they analyzed cases from a single box. With any manufacturing process, they have ranges. It could just be that these particular boxes analyzed were at the opposite ends of the range and do not necessarily represent any change in the process.

It is also my understanding that the only cases that have thinner necks are the 6mmBR. It was not an across the board change at Lapua. These cartridges had been manufactured to the thick side of the range and sometimes went over spec. They needed to change the process to avoid this so they would retain a shooting industry certification.

 

[dmoran]

to AndyTaber and CSM19Z5M -

Explain to me how from 2004 to 2009 (my years of using gold box) all the boxes and Lots of gold box would consistently blow 6Dasher's for me to +1.556" and never hurt a primer pocket, to since then (2009) on the blue box ever since its been a struggle to get blow lengths to 1.545" with pour consistency and are easy to hurt/stretch the pocket?

As I described above, shooting both at the same time, same load, and firing them simultaneously, they did not blow any where near the same, so how are they the same as you claim?
Have you used both yourself?

I've used at least 6 Lots of each over the years, and can honestly say they act like 2 completely different brass types to me. Both have acted very consistently the same from Lot to Lot, but not to each other at all.
Donovan

 

[johara1]

Donovan, +1 on what you stated, gold box ….. life was good but Blue box life is a struggle. Flash holes vary .004, neck wall thickness varies from - .011 to over .012, primer pockets are tight to loose when new. and to get any length of 1.550 is a struggle, and uniform length is a key to accuracy. When you split a shoulder fire forming it is usually a defect in the case and i've found cases that look like a rivet ……. one step forward and two back…….. jim

 

[snakepit]

Lapua says they are the same brass just different box.

That is not what they said. The blue box brass was purposely made with thinner necks as Lapua's loaded ammo was too close to CIP maximum diameter. That was posted here numerous times by Kevin Thomas from Lapua and measured by many of us. Look it up before you spread your delusions as the truth.

I would like to read some of those post from Kevin Thomas that you refer to since they seem to differ from the one quoted in a prior post. Could you please post them or direct us to them so we can read the statements. Like I said I do not have a dog in this fight and I am too new at this to have ever used the gold box brass, only the blue box but now I am curious to what Kevin Thomas of Lapua really said.

 

[dmoran]

snakepit -

There's no "fight" with me either, just stating what I personally seen between the two.....
Don't really matter, the gold/brown box days are long gone and besides I've been on "blue box" ever since the switch. They work fine, just had to make some changes to the way I form them and to my chamber length. And clean and watch for carbon with short blown cases....
Donovan

Here is the link your asking for:
http://forum.accurateshooter.com/index.php?topic=3841802.msg36384234#msg36384234

 

[johara1]

Maybe i'm Technically challenged……. but explain to me if neck was only .001per side, i have a 1000 that is less than .011 per side to start with? and they are over .010 shorter than the gold box stuff? and the copper to zinc mix has changed? sounds like somebody is covering their tracks or blowing a little smoke…….. jim

 

[dmoran]

There were a number of us 6Dasher users who experienced the same thing back then (2009/2010) between the old cardboard boxed and newer blue plastic boxed brass. And that was it didn't act like the same brass when we formed it. Then besides our experiences, there was the "X-Ray Spectrometry of Cartridge Brass" report, that kind of backed up what many of were stating.

To me the difference to forming 6Dasher's between the two era's was a significant difference. Every method and load that I had been using for years prior, did not work out to any brass coming from the blue box's and hasn't yet to this day. The three variance aspects for me are/were:
1 - blow length variance
2 - consistency of the blow lengths
3 - primer pocket variance

The down side, I am not able to get as long of blow lengths, as consistent of blow lengths, and can stretch/hurt the primer pockets more easily, after the switch in containers (cardboard to plastic <> aka: gold to blue).

The upside, I don't see no difference in accuracy potential, and get good brass life from the blue box era also, as long as I stay a little gentler on the charges. Also have to clean and monitor for carbon more when using shorter blown/formed cases.

Just confirming what I seen and experienced personally, and don't really care what others claim.
There is/was a significant difference in every one that I pulled from cardboard boxes then ones I have pulled from the blue plastic boxes (2004 to 2009 -verses- 2010 to present) and formed to 6Dasher since.
Donovan

 

[johara1]

Donovan, I also changed reamers to use the thin necked,short brass. I went from a .269 neck to a .266 and shortened up from a 1.570 chamber to a 1.560 chamber length. Like you said both worked good but i seem to think it cost me more than brass maker plus a lot of work……jim

 

[dedeadeye]

Donovan, absolutely 100% correct. Roger

 

[Terry Altom]

I'm building my first Dasher and after consulting with Master Jedi O'hara and reading on Accurate Shooter, I spec'd out a .267 neck with 1.565 chamber length reamer from PT&G. I'll find out in a few weeks if I chose wisely.

In the mean time, I'm saving all of you guy's tidbits of experience to help me avoid needless week and months of experimenting. Much appreciated!

 

[johara1]

I'm building my first Dasher and after consulting with Master Jedi O'hara and reading on Accurate Shooter, I spec'd out a .267 neck with 1.565 chamber length reamer from PT&G. I'll find out in a few weeks if I chose wisely.

In the mean time, I'm saving all of you guy's tidbits of experience to help me avoid needless week and months of experimenting. Much appreciated!

I don't know about the master jedi bs. I'm just an old fart that likes to shoot small groups with a Dasher and like to pass on any info. i learned before i pull my last trigger……….. jim

 

[Terry Altom]

Jim,

If you happen to read this, how often do you clean your chamber with non-chlorinated brake cleaner when you're fireforming new Lapua brass to Dasher? One and done or every so many rounds?


Thanks much,
Terry

 

[johara1]

Terry, I clean the chamber every 5 rounds, the carbon in the neck area makes the cases short. I don't worry about how well they shoot, i shoot them in to a bank outside the basement door. What i look for is uniform blow length of a few thousands and FF. is the only way you can get it. If you don't hurt the cases with excessive pressure they will last for a 100 firings, so i'm not concerned with using a bullet that don't shoot anyway or powder that i can't get to work and a primer i will not use in anything but FF………. jim