These two cartridges are driving me crazy.

Now that Ken Howell's cartridge recognition book arrived, I find that I do not find the Norma BR in it.

Can someone please be so kind and enlighten me ?

Thank you.

The 6mm Norma BR is the 6mm Remington BR re-developed.

The 6mm Remington BR was developed in 1978 by Mike Walker.

The 6mm Remington BR was standardized in 1988 by Remington.

Norma "adopted" the 6mm Remington BR and decided to make it their proprietary cartridge by modifying the throat to accept 105 to 107 grain bullets. They also respecified the OAL to 62mm. They then went and changed the twist to 1:8.

Norma did all this around 1995.

There is loading data for both at:
http://stevespages.com/page8c.htm

This is a quoted response from one of the more knowledgeable people at Benchrest.com:

[QUOTE] This comes up more often than any uestion asked here.

This whole 6BR, 6BR Remington, 6BR Norma, and Lapua 6BR Norma must be driving everyone nuts. I think Wilbur should dedicate a seperate side-bar in the FAQS section to just this question. But here it is.
When Remington first announced the BR case, they didn't make brass for it. They did make a case known as The Remington Benchrest Case, which was a thin walled, 308 sized affair with a small rifle primer. Shooters formed a nominal length case of about 1.5 inches with a 30 degree shoulder out of this brass. It looked surprisingly close to a fat PPC. Later, Remington decided to make the brass and offer it as a factory item, but settled on an over all length of 1.560, the added length being in the neck. This was ok, all shooters who were in possession of the older rifles had to do was trim back the neck length.
Later on, Norma started making brass for this chambering, it was physically the same as the Remington and worked fine. But then, Lapua came along and started making the cases. The only stick in the mud was that the head diameter just forward of the extractor groove on the Lapua case was larger in diameter by almost .002 inch. (if you check Lapua .243 or 308, they are also larger than all others at this point). Since a lot of shooters had MINIMUM spec chambers that fit the Remington and Norma cases perfectly, shooters were finding that the new Lapua Brass would not go in. (there didn't seem to be a problem with the factory chambers in thr Rugers and the Sako's). But since the Lapua Brass is considered by many to be far superior to anything else out there, reamer grinders started grinding tools that compensated for this added diameter, hence the Lapua 6BR Norma. (I have no idea why Lapua still puts Norma on the head stamp, must be a legal thing). Ballistically, there is no difference in any of them, except that the 1.560 case length does have a slight more powder capacity than the originol 1.5 length. If you have a Rifle built now, tell your Gunsmith that you will be using Lapua Brass, (I can't amagine using anything else, unless cost is a BIG factor). I would hope that by now, every Gunsmith on the Planet knows that the older minimum spec reamers might present a problem if they were ground to the originol Remington specs. Wilson and Redding are also making dies that specifically fit the Lapua case, but can still be used to load the Remington and Norma. I hope this helps explain all of this.
By the way, this happens to everyone sooner or later. The very first "Benchrest"(kinda), rifle I had was a 6BR. When Sinclair started offerring Lapua Brass, I got some, and guess what, it would not go in. I believe that they even ran a discalimer in their catalogue explaining the whole problem....jackie

__________________
jackie schmidt

IMHO:
If you're going to shoot 6BR have your smith cahmber the rifle for the Lapua brass(headstamped 6BR Norma). You won't regret it.

My rifle has the standard 6BR Norma chamber with a .272" neck. I just load 'em up and shoot! The loaded round neck diameter is .270".

HTH,

Mark