6mm Norma vs. 6mm ????

[CjC73]

I'm sure it has been explained numerous times and I've read more than a few articles on this, but cannot get a clear answer (at least to me).

What is the difference between the 6mm BR and 6mm Norma and 6mm Dasher?

I see a rifle I'm interested in and it's labeled as a 6mm Norma (and it comes with dies). One question I have is brass readily available for this caliber or does it need to be fire formed? And if brass is available, would it be ready to load right away? no neck turning or whatever.

I guess I'm just curious as to if this caliber is good for a casual shooter looking to bang steel. Or should this be left to the 'serious' competition shooters?


thanks for your assistance

 

[Laurie]

There is a great deal on this site covering this, but to summarise:

6mm BR Remington is the original form of the cartridge. It has a short freebore, slow rifling twist and uses light bullets for varminting or short-distance BR. Its case is close to that of the 6mm BR Norma, but marginally smaller diameter in the lower body, likewise its chamber. Brass has long been unobtainable and its chamber reamers should not be used as the resulting chamber gives an over-tight fit with today's brass.

6mm BR Norma is an updated variant of the cartridge introduced by Swedish company Norma Precision in 1996 and registered with the European standards body the CIP. It uses an near identical case to the Rem version and has a slightly tighter chamber in the lower body area. It has a great deal more freebore and is specified for a 1:8 twist. It therefore handles heavier / longer bullets and was intended not as an out and out BR Cartridge but more with 300 metre ISSF / CISM in mind by Norma. With high-BC 100-108gn bullets it is a competent F-Class, mid/long-Range BR number out to 1,000 yards. Todays' brass (by Norma and Lapua) are for this version and are available most of the time.

The 6mm BRA, BRDX, Dasher and various other forms are wildcats / improved versions of the 6mm BR Norma using its factory cases as the starting point. Specify a Dasher reamer and the factory brass is fireformed to a new shape in the resulting chamber with the shoulder blown forwards and the neck-length reduced. Not quite as simple as this but that's the essence - one of the best mid and long-range BR cartridges around and holder of many records.

 

[CjC73]

ok, thanks. that was sort of what I thought as well. So a 6mm Norma is a 'standard' caliber, meaning you can buy brass readily. And the Dasher and others you mentioned are the wildcats based off the Norma.

 

[Laurie]

ok, thanks. that was sort of what I thought as well. So a 6mm Norma is a 'standard' caliber, meaning you can buy brass readily. And the Dasher and others you mentioned are the wildcats based off the Norma.

Yes and yes. Here are the basic guides from elsewhere on Accurate Shooter and a bit old and dated now, but there is far, far more available on here if you want to dig - tens of thousands of words.

http://www.accurateshooter.com/cartridge-guides/6mmbr/

http://www.accurateshooter.com/cartridge-guides/6mmbrimproved/

The latest variant is the 6BRA, for which there are already around 90 separate topics on the Accurate Shooter Forum and mentions in the Daily Bulletin.

 

[dkhunt14]

I'm sure it has been explained numerous times and I've read more than a few articles on this, but cannot get a clear answer (at least to me).

What is the difference between the 6mm BR and 6mm Norma and 6mm Dasher?

I see a rifle I'm interested in and it's labeled as a 6mm Norma (and it comes with dies). One question I have is brass readily available for this caliber or does it need to be fire formed? And if brass is available, would it be ready to load right away? no neck turning or whatever.

I guess I'm just curious as to if this caliber is good for a casual shooter looking to bang steel. Or should this be left to the 'serious' competition shooters?


thanks for your assistance

The neck turning part depends on what neck it was chambered with. Then you have the new Norma Reamer that Shariz came out with or the old Lapua, Norma type. Shariz made the brass longer. Both those brass are available but if you use Shiraz Dasher brass in a Lapua chamber, they will have to be trimmed. They are already formed for a Dasher and will work in either chamber but have to be trimmed for the regular Lapua or Norma chamber. Matt

 

[Laurie]

The neck turning part depends on what neck it was chambered with. Then you have the new Norma Reamer that Shariz came out with or the old Lapua, Norma type. Shariz made the brass longer.

I'd forgotten about the Shiraz / Norma off the shelf long-neck Dasher brass. It seems to have gone very quiet recently on this topic after having something (if not 10 somethings) posted daily for months on end.

I have just a tiny suspicion that the few I know in England who've gone down that route, special reamer and all, are appreciative of the absence of the need for neck turning, fireforming, annealing etc ...... but aren't as happy with their rifles' performance with it as they expected.

 

[Lynn313]

ok, thanks. that was sort of what I thought as well. So a 6mm Norma is a 'standard' caliber, meaning you can buy brass readily. And the Dasher and others you mentioned are the wildcats based off the Norma.

You can get very high quality brass from Peterson and Norma for the 6 dasher......ready to load. Norma has made brass for Lapua and then had Lapua stamped their name on it.

 

[jackieschmidt]

The current 6BR manufactured Norma and the one manufactured by Lapua do differ in one major area in that the Lapua case, which has “6mmBR Norma, Lapua“ on the head, measures about .002 larger at the web.

 

[Lynn313]

The current 6BR manufactured Norma and the one manufactured by Lapua do differ in one major area in that the Lapua case, which has “6mmBR Norma, Lapua“ on the head, measures about .002 larger at the web.

Thanks for that info. The Norma cases made for Lapua to be stamped Lapua were the belted magnums I believe.
I’m getting parts to build my 1st 6 dasher. I would think I should just keep quiet and read, but if not posting something I would not have learned this.
I think Norma and Peterson are the only ones making good dasher brass. Is that correct and is there any difference between the two.

 

[swd]

Thanks for that info. The Norma cases made for Lapua to be stamped Lapua were the belted magnums I believe.
I’m getting parts to build my 1st 6 dasher. I would think I should just keep quiet and read, but if not posting something I would not have learned this.
I think Norma and Peterson are the only ones making good dasher brass. Is that correct and is there any difference between the two.

The Norma Dasher is slightly different and has a .050" longer neck. It's also slightly smaller at the back end. Peterson is based more on Lapua spec.

 

[Lynn313]

The Norma Dasher is slightly different and has a .050" longer neck. It's also slightly smaller at the back end. Peterson is based more on Lapua spec.

swd, I don’t find 6 dasher brass on Lapua’s website. Did Lapua once make dasher brass

 

[swd]

swd, I don’t find 6 dasher brass on Lapua’s website. Did Lapua once make dasher brass

No Lapua doesn’t make Dasher brass but probably 95% of the Dasher brass out there has been formed from Lapua 6BR brass hence most reamers are specked for that particular brass.

 

[Webster]

I'm sure it has been explained numerous times and I've read more than a few articles on this, but cannot get a clear answer (at least to me).

What is the difference between the 6mm BR and 6mm Norma and 6mm Dasher?

I see a rifle I'm interested in and it's labeled as a 6mm Norma (and it comes with dies). One question I have is brass readily available for this caliber or does it need to be fire formed? And if brass is available, would it be ready to load right away? no neck turning or whatever.

I guess I'm just curious as to if this caliber is good for a casual shooter looking to bang steel. Or should this be left to the 'serious' competition shooters?


thanks for your assistance

Wihout going to a reloading manual a looking at the case lenght. I have owned a 6mm Rem, a 6BR and a 6BRX. Keep in mind the the 6mm Rem BR is not the 6mm Rem. The 6mm Rem was a longer cartridge that holds a lot more powder than the 6BR Norma.

 

[Tokay444]

Wihout going to a reloading manual a looking at the case lenght. I have owned a 6mm Rem, a 6BR and a 6BRX. Keep in mind the the 6mm Rem BR is not the 6mm Rem. The 6mm Rem was a longer cartridge that holds a lot more powder than the 6BR Norma.

Other way around. 6BR Norma is longer and and throated longer for longer heavier billets. The case itself is also .04” in the Norma.
Edit. My bad. Yes. 6mm Rem is larger than all the BR. I read that too quickly.

 

[Webster]

Other way around. 6BR Norma is longer and and throated longer for longer heavier billets. The case itself is also .04” in the Norma.
Edit. My bad. Yes. 6mm Rem is larger than all the BR. I read that too quickly.

The cartridge is not throated, the chamber is.

 

[CJ6]

6 mm Remington = based on 7 x 57 mauser. 6 Br's based on the 1.55"+ or - BR CASE

 

[Tokay444]

The cartridge is not throated, the chamber is.

Yeah I didn’t say the cartridge was throated long. I really didn’t say much of anything. That post is terrible.

 

[LRPV]

Alpha makes Dasher brass as well that is spec'd closely to Lapua formed cases.

 

[Lynn313]

The Norma Dasher is slightly different and has a .050" longer neck. It's also slightly smaller at the back end. Peterson is based more on Lapua spec.

Good information. Sounds like I need to pick which brass to use before cutting chamber. From the other posts I take it most 6 dashers are chambered off the Lapua standard. The gunsmith I plan on using also mentioned liking Peterson brass.

 

[Webster]

The current 6BR manufactured Norma and the one manufactured by Lapua do differ in one major area in that the Lapua case, which has “6mmBR Norma, Lapua“ on the head, measures about .002 larger at the web.

There may be a SAAMI standard for 6PPC, BR ect. But there are variation due to serious shooters wanting a different throat angle and other things. A fired 6BR Lapua case will not come close to chambering in my 6BRX. I have to fire form with a new case. Plus the reamers have a +/- tolerance when they are ground. The only one I can think is the Speedy Gonzales 6PPC reamer spec. PPG probably has many 6PPC custom reamers. Jim Kelby told me many times they have to specify reamer dimensions and not just order the popular drawing.