Al Nyhus
Charter Member
14 posts
Nov 21, 2004
9:01 AM
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Just a note on the latest lots of Lapua 6BR cases...Sunday mornin' ramblin' from the 'Forbidden Zone', if you will.....
It appears that latest cases imported have some dimensional differences from the 'early' Lapua 6BR cases.
The early cases have a base dimension of .4705-.471 and a shoulder /body dimension of .4595-.460. The latest cases have dimensions of .4685-.469 and .458-.4585 respectively.
This should allow better chambering with chambers cut for the 'original' Remington 6BR brass (either the early 1.520 or the later 1.560 'long neck' length version). I have a 'Rem. spec.' BR chamber in one of my guns that needed the Lapua .471 case run thru. the standard Redding Body Die before it would chamber, but the 'new' Lapua cases fit w/o this step.
Additionaly, the 'new spec.' brass seems to work well in the chambers cut for the early Lapua 6BR brass...what I now refer to as the 'Lapua .471 case'.
Looks like Lapua really got things right with their latest change.
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DANTEC
Charter Member
67 posts
Nov 21, 2004
9:17 AM
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CIP specification are 0.471 chamber
IF lapua make smaller base they are WRONG and that not safe at all because 6 Norma is hight pressure case ( short case ) so keep case base very close to chamber is very important to kep primer pocket tight
OLd REM specs are design to be close to 22.250 case base , that now a piece of history , and Norma Lapua brand seem to be the standard in avaibilty
IF I get such cases as it in Europe I will be very "happy" to send back the junk case straight to the Lapua factory and make a very nice adds on Lapua brass quality
Good shooting
DAN TEC
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jb1000br
1000yd Editor
60 posts
Nov 23, 2004
8:20 AM
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measured several--.4687-.4689
JB
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Al Nyhus
Charter Member
15 posts
Nov 23, 2004
2:57 PM
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JB, for what it's worth...I run the 'new spec' Lapua 6BR cases in my 30BR with no problems. The 30BR chamber is cut with the Kiff 30BR 'Robinett' spec. reamer which is ground for the '471 Lapua' cases.
The 30BR runs at pretty high pressures....118's at 3020-3040 fps. Some experimental loads with H4227 Extreme pushed the 118's to 3,200 (eeek!) with exceptional accuracy before expanding the base of the case past the point where I could resize it. Despite all that, the primer pockets remained tight.
Actually, the new spec. Lapua cases work out better for sizing in a Redding Body Die with the '471' chambers.
BTW...congrats on your recent match win! There are 'talkers' and 'walkers'. You do both....good job! -Al
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James n TN
5 posts
Nov 23, 2004
3:39 PM
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Al,
I have contacted Don Golembicski The tech rep for Lapua in the US and he is checking on why they have changed dimensions on the case. He did say this is the first he had heard of this and was curious to why there is a change. He told me he would get back with me as soon as he hears back from them. This bothers me as I had just gotten a new reamer made for a 6 Dasher and my reamer was designed on the old case dimensions.
If you hadn't heard That little ole 22 dasher I have got me a heavy gun world record at 600 yds for a 1.190 group single target group.
James
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Al Nyhus
Charter Member
16 posts
Nov 23, 2004
7:29 PM
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Hi James. Congrats on your pending IBS World record! I know you hung in there through some frustrating times...that will make this all the sweeter for you.
Actually, I think that what Lapua has done (I'm assuming it's intentional) makes a lot of sense. Even with a .471 chamber, we still have .002 clearance on the back end. Anyone that has messed with these BR chambers, regardless of brass, can tell you that it's the front (shoulder/body junction) that can give a guy some gas when it comes to sticky cases.
Again...congrats. -Al
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James n TN
6 posts
Nov 23, 2004
7:42 PM
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Al,
Thanks, You are correct I had caught some tough times and alot of flack over some of the groups I had posted in the past. Now that I have actually done this in a registered match it does make all that other stuff worth while and much sweeter and maybe I've gained a little respect in my abilities to shoot them tiny groups. I know I have woke a few up on what the 22 Dasher is capable of.
For this case dimension change in the Lapua brass for me I think it's a bad move on there part. Theres a spec for this brass and it has been established. Now that i have had a reamer made on the old dimensions I just hope it don't create any problems. I guess best thing I can do now is hord up as much of the older stuff I can find.
How has your 2004 season gone? I hadn't kept up much with the point blank shooting as I had also began a new business venture and have been busy with this the past few months. Check it out sometime you get a chance my ad is over on the GGVG board maybe I can help save ya a few bucks in the future.
Hope you and your family have a safe and wonderful holiday season.
James Phillips
Reloaders Nest
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jb1000br
1000yd Editor
61 posts
Nov 24, 2004
9:58 AM
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Al--thanks for the good words!!
I'll run what i have and see how it goes--i plan on pushing here pretty hard (of course) so we'll see how they hold up.
BTW--have you seen the note on the lapua boxes to the effect "these brass cases will last 10 reloadings or more"
sounds like a challenge to me :D
JB
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