Which 6BR should I build?

[fatelvis]

I'm thinking about building a 6BR rifle for F-class. I see Shilen pre-chambers their barrels with either 6BR Norma, 6 BR Rem, or 6BR Rem .263" . Which is the most common, and which is best in your eyes when using 105 Berger Hybrids? Thanks!

 

[fatelvis]

I just realized that the .263" is the neck diameter. I assume that is considered a "tight neck" chamber and the brass must be neck turned?

 

[Dusty Stevens]

Only go with the norma

 

[SSeal]

^^^^^Yes Norma is the new standard. ^^^^^

 

[NorCalMikie]

Only go with the norma

Zero free bore, .272 no turn neck and start with the lightest bullets you can get your hands on then go heavier as the throat wears, and it will. Probably faster than you'll want. And I forgot, 8 twist.

Years back, I got a Shilen barrel with an off the shelf 6 BR chamber cut. Big mistake on my part BUT, you learn as you go. Nothing wrong with the barrel except you couldn't get anywhere near the lands with 50 grain bullets. I prefer my bullets jammed into the lands. It was still a bug hole maker. Sold it to someone that wanted to shoot heavier bullets. From then on, nothing but custom cut chambers for me. Either get it the way YOU WANT IT or pass till you can find what YOU want.

 

[JFrank]

My preference- 6 Norma 272 no turn with a minimum of a 1-8 twist and around .93- .104 Freebore , sample as many 105 class Bullets as you can

 

[Dusty Stevens]

I just realized that the .263" is the neck diameter. I assume that is considered a "tight neck" chamber and the brass must be neck turned?

Actually the 273 lets you know what it is for future reference. .269 used to be no turn, then .271. It reminds you to measure a loaded round. Todays lapua and norma though 273 is a good no turn

 

[rwj]

I just realized that the .263" is the neck diameter. I assume that is considered a "tight neck" chamber and the brass must be neck turned?

On the last two lots of Lapua brass I bought, the neck OD measured .269” with Berger 105 VLDs loaded into unturned cases...

 

[fatelvis]

As usual, thanks for the quick and concise assistance guys!

 

[Bill Norris]

On the last two lots of Lapua brass I bought, the neck OD measured .269” with Berger 105 VLDs loaded into unturned cases...

rwj - My last 2 lots of 100 pcs. is exactly as yours and when doing a very light neck clean up they are still at @ .2685 or so.

 

[Big Mc]

I'm thinking about building a 6BR rifle for F-class. I see Shilen pre-chambers their barrels with either 6BR Norma, 6 BR Rem, or 6BR Rem .263" . Which is the most common, and which is best in your eyes when using 105 Berger Hybrids? Thanks!

I have a >272 no neck turn with Lapua brass .103 freebore . won many club matches. It is my choice. Tommy Mc Plane jane 6mmbr Norma

 

[johara1]

Those short free bores are worthless with the 115 Berger and very marginal with a 105 if you need velocity and want to use a bulky powder and if they shoot in the lands or are jumped. It is not a one size fits all, You need a .140-.150 for the 115 Berger then that is all that will work. Go with a .110 - .115 for the rest, 110's and 105 will work, you got to keep the heel of the boat tail up in the neck and above the non sized part...... jim

 

[butchlambert]

What difference is there between the 6br Norma and the 6br Remington?

 

[Eric Leonard]

What difference is there between the 6br Norma and the 6br Remington?

Neck length most I think

 

[boltman13]

The cartridge drawings in the Berger Reloading Manual are very similar but not exactly identical. The main difference is the 6BR Norma chamber is cut to allow the longer, heavier 6mm bullets to work properly in a 1:8 or faster twist barrel for longer range competition and the 6BR Remington chamber is cut to allow proper chambering of the shorter, lighter short range Bench Rest bullets in a slower twist.

 

[Tommie]

Isn’t the Norma version a few thou larger at the base?