Lapua 6MM BR Brass, old vs. new

[ehkempf]

What is the average neck wall thickness of the old paper box 6MM BR brass vs. the new blue box?

Thanks,

Ed

 

[RCurtis]

If I recall correctly the new is nearly .002" thinner.

Rick Curtis

 

[FroggyOne2]

That is what I came up with Rick.

 

[ehkempf]

If I recall correctly the new is nearly .002" thinner.

Rick Curtis

Not sure what you mean by that answer. What I am looking for is wall thickness, such as .014, .013 etc. With the measurement that you gave, do you mean that a loaded round measures .002 thinner with the blue box, or do you mean that, for example, that old measured .014 and new measured .012.

 

[KevinThomas]

Thanks Dave. Saved me the trouble, and you're spot on.

 

[Barlow]

Just got a box of them yesterday. Measured 10 of them at .013- .0135. Barlow

 

[Blaster-37]

I agree with Dave Berg. I have use many of both.
In my experience, the gold box will fully turn down to 12 1/2 to 13 and the blue box will turn down 11 1/2 to 12 1/2. I use the 21st Century lathe.
I have less casualties with the with the gold box. I shoot them hard and loose about 10% of the blue box and 3% with the Gold Box every reloading. I anneal every time, and yes I have tried less annealing. Most of the casualties are neck/ shoulder splits and case "black line" separation. I have seen many of these "black line" case separations occur to fellow competitors during the match, it is not pretty. If I can see this line clearly or inside and out, it's gone. This separation line is usually about 1/3 from the base and occurs much less with the gold box, even after 10 shootings.
My favorite chamber is a .269 neck. I prefer the fully turned neck that the gold box can achieve. When they run out, I will probably go to the .268 neck for the blue box.
The gold boxes are still out there. I missed a new gold box yesterday on GunBroker that sold for 75.00. I have purchased them by the case as recent as last year and dispersed many to fellow Deep Creek 1k plinkers. No, I do not want to sell any more, get a new reamer.
I believe the really great groups started on the loading bench with absolute consistency. Perfection is unobtainable... it is your decision as to what is good enough.
Yeah, I know, that is sick.
Greg

 

[Barlow]

I just weighed the blue box I received yesterday.
125.8 = 2
125.9 = 6
126.0 = 5
126.1 = 22
.2 = 22
.3 = 20
.4 = 13
.5 = 7
.6 = 2
.7 = 0
.8 = 1 Barlow

 

[CatShooter]

Do you guys think 269 loaded round is safe in a .2705 chamber? Ive always had atleast 2-3 tho clearance in the past.

An 0.269" neck is only 0.0015 smaller than a 0.2705" chamber neck. A 3 thou clearance would need a 0.2675" neck.


I have a 0.2620" neck 6mmBR and I first shot cases that were 0.2613" (0.0007" clearance), and quickly discovered that I had created a monster. It was "safe", but groups opened up fast as ash collected in the neck and changed the release pressure - I had to clean it every 10 shots.

I re-cut the necks for a total clearance of 0.003", and it became a complete kitty cat to shoot.

.

 

[areaone]

I have done it, but do not reccomend it.

 

[Blaster-37]

Again, I agree with Dave. I also run .0015 clearance for fully turned necks and it works well for me.
Greg

 

[Old Navy]

I have less casualties with the with the gold box. I shoot them hard and loose about 10% of the blue box and 3% with the Gold Box every reloading. Casualties are neck/ shoulder splits and case "black line" separation. Greg

What are you shooting that destroys so many cases? Later! Frank

 

[Blaster-37]

I have less casualties with the with the gold box. I shoot them hard and loose about 10% of the blue box and 3% with the Gold Box every reloading. Casualties are neck/ shoulder splits and case "black line" separation. Greg

What are you shooting that destroys so many cases? Later! Frank

Top node in the 33+ gr. Lately I blame the wind for blowing them off the bench, bent necks, etc.
Greg

 

[James EPS]

I had a blue box of brass I used this year when I built my BRX and fireformed 30gr of varget and ruined my primer pockets loosened up and had blow by after 5-6 fires.

So I had 3 card board boxes here and decided to try some, loaded 28 grs fire formed nice tight primer pockets now still after 3rd firings. I really didn't want to turn the necks unless I absolutely had to. I make my own 6mm 106gr bullets the measure .2430 so far. Like Dave mentioned when I get my die polished in the future I have some wiggle room.

I will just have to keep my eye on things ie keep barrel clean and such. Back in my PPC shooting days it was common to shoot things tight like that but 133 was nice and clean so I never really had any issues so I figured as much with the BRX.

Thanks for every ones input.

James

 

[Rustystud]

Not exactly comparing apples to apples. I have 3 6mmBRX reamers.

1. .272 no turn neck .104" FB

2. .271 no turn neck .090" FB

3. .268 turn neck w/ .040" FB

I use a 1* 30 throating reamer if my throats need to be extended.

I see little difference in accuracy in any of theses chambers.

My personal loading preference is using a .266 bushing.
I now anneal with every reloading.
Starting with 300 pieces of virgin Lapua brass. My brass life exceeds exceeds my barrel life.
That means 16-20 reloadings. Obviously I don't shoot excessive loads nor do I exercise my brass much.
With the new Lapua brass being on average .002" smaller one would think there would be some visible differences seen using the .271 neck chamber. I have found running a to tight neck causes flyers in the BRX.
Annealing has dramatically improved my groups.
Have a customer shooting 31.25" Rock Creek 1:8, 5R barrel who shot two back to back 4" 10 shot groups at 1000 yds with a .272 neck 104 FB chamber shooting Blue Box, once fire formed Lapua brass.
It would be interesting to see if anyone is shooting a .270" neck with any better results.
Nat Lambeth

 

[rvn1968]

I think we can quit bitching about the differences between the great "old gold" and the blues(bad pun). We are unable to turn the clock back and now we have to play the cards dealt.IMHO Tom

 

[FroggyOne2]

The blue box 6BR brass is working out real well with my 22BR project!