Home Forums Hunting & Shooting Custom Rifles & Wildcats Need info off Lapua 7x64mm Brenneke cases

Working on a "project".

If someone with NEW, Lapua 7x64mm Brenneke brass could tell me the actual neck wall thickness (average that is hopefully uniform like most their brass)..........it would be appreciated.

Actual base and rim diameters too would be of interest. Might wish to buy a couple plus shipping depending on that info, for tests. (I will put in a classified ad, Dear Mods, don't hammer me, please.)

To be clear, measured information off cases in hand.

God Bless
Steve

Sample of ten straight from packet using Mitatoyo digital caliper in just the mouth of the case, most miked in at .030 mm (.012") with one going .033 mm (.013") and one at .032 mm.

For kicks I also checked new RWS and they went at .030 mm-.031 mm.

Note that none of these were chamfered outside of factory.

Rims at .0435", base at .4655", solid case head at .464".

With RWS rim at .048", and base at .4665", solid case head at .462".


Should also mention that 308 shell holders are too tight, so unless you wish to resort to a Dremel you will find it expedient to source a set of Redding #07 competition shell holders, or a single #07 if you wish.

Thank you very much. I really appreciate this information.

God Bless
Steve

The rim diameter for 7x64 Brenneke, if I am correct as I can't find my CIP data sheet right now, is .470 diameter and rim thickness is .051. For comparison the 280 Remington is rim diameter of .473 and rim thickness of .060. Lapua brass is made to CIP specifications as far as I know. CIP is exact and by law, SAAMI is not always the same. I don't have the specs to see what the base of cartridge just above the rim is supposed to be. Hope this helps. I never understood why the variation in rim thickness. A 284 is .040 and a 7x57 is .045. I have never read why the differences.

edit with additional info:

I read once that the 7x64 was developed from the 9.3x62. The 9.3x62 was created around 1905. That cartridge (the 9.3) also has a rim diameter of .470. I do have that diagram and the base of the cartridge above the rim has a diameter of .476. There is a good chance that measurement also fits the 7x64.

Ever measure the rim diameter of US made rounds?
While most are quoted as .473.......it's been a LONG time since I've measured one that "large".

I've always ASSUMED, right or wrong, that the MINIMAL measurements Ive seen for quite some time in almost every single area of the brass case was, at one point, a "money saving decision".......due mostly to what I've seen occur in 45 years of factory work.

Many put aside the fact that SAAMI specs are NOT carved in stone.

Keeping in mind that SAAMI includes "Arms Manufacturer's" in the acronym and NOT a governing organization but a voluntary one (who's voting members include all ammo manufacturers) I think they can pretty much do what their attorneys will tell them is "safe" responsibility wise.

I gave up looking at SAAMI info as anything but a ballpark estimate decades ago. Not a complaint.....just my observation.

Just my 2 cents.

Thanks to all
I think another round is going to give me more what I'm looking for.
God Bless
Steve