6mm BR

[shrek]

Hi guys im looking for some advice im planning on having a 6mmBR built however what is the difference between 6mmBR Norma or Rem is one or the other more accurate and which one would you guys with knowledge of the calibers go for?

 

Also to get a variation on my ticket for one can i be cheeky and just put down 6mm BR for the variation so i can have a choice or will they pick it up that there is 2 different calibers?

 

Cheers

[baldie]

Just put 6mmbr down mate, they arent different calibers, just different throats. It all depends on its intended use, and preffered bullet weights, this in turn determines barrel twist rates. I have a 6mmbr norma, which has a 1 in 8" twist 28" tube on, and its throated specifically for the berger 105 vld bullet.This is a std sort of set up for a target rifle, a sporter would use lighter bullets and a slower twist.

I believe cooper arms are about the only ones still using the 6mmbr remington chambering reamer, its the original chambering and its old. The chambering was standarised in 1983 if i remember rightly, to 6mmbr NORMA.Anyway, thats a very rough idea, check out this excellent site, it will give you all the info i,ve just written, but it will be correct where my memory has undoubtedly failed!

 

http://www.6mmbr.com/6mmbr.html

[shrek]

cheers baldie, good to get that cleared up, u'll probably know better than me how endless licencing can be, if its not a normal for the area caliber (243, 270, 308) then they dont have a clue! cheers anyway!

[Vermincinerator]

Baldie,

My Cooper is marked 6mmBR and chambers Lapua brass, so i think it can be safely said that it is the now standard 6mmBR Norma chamber.

 

Ian.

[baldie]

Really? They must have switched fairly recently Ian, in the last two years anyway. I actually had one on order with brian fox two years ago, but cancelled it when i realised they still used the rem chamber [then] and it was a 1 in 14" twist.I couldn,t see why they were still doing it, when the round had been standardised in the 80,s, so not wishing to encounter problems, i built my own.

Its a fabulous cartridge full stop.

[Vermincinerator]

Baldie you are right about the 14 mate, however my rifle pre-dates your order as mine was one of 3 6mmBR's Brian got in his first ever shipment from Cooper.

I emailed Cooper before i bought and was told that it was a SAAMI spec chamber that will chamber Norma ammo, i asked "why then a 14 twist barrel" and was told i could have specified another twist rate but at a premium.

With 68grn Bergers it prints sub 3/4 moa 5 shot groups at 400yds

 

Ian.