6BR old Remington-Peters brass

[xpilot]

Did the old R-P brass have a shorter neck than the current manufacturers ?
I have acquired an older remington 700 with custom bbl marked "6BR remington" The old R-P case chambers fine, new Lapua will not. (same neck dia) Older neck approx .035 shorter. Any thoughts?

 

[hogpatrol]

From the 6br page:

The 6mm BR that is most commonly used today is also called 6mm Norma BR, “6BR Norma”, or just plain “6BR”. Norma started with the 6mm Remington Benchrest and increased the base dimension slightly. But the official SAMMI cartridge OAL is the same: 1.560″. (However Remington did originally produce brass at 1.520″ OAL and some older chambers have been cut to a shorter length.) Though Norma standardized the round, most people shoot Lapua brass, because of its superior quality and uniformity, not to mention lower cost. The case capacity of Lapua brass is about 38-39.5 grains of H20, after fire-forming. The exact capacity depends on your gun’s chamber and the brass lot.

It would seem you have the shorter chamber but a chamber cast would verify it.

 

[CatShooter]

From the 6br page:

The 6mm BR that is most commonly used today is also called 6mm Norma BR, “6BR Norma”, or just plain “6BR”. Norma started with the 6mm Remington Benchrest and increased the base dimension slightly. But the official SAMMI cartridge OAL is the same: 1.560″. (However Remington did originally produce brass at 1.520″ OAL and some older chambers have been cut to a shorter length.) Though Norma standardized the round, most people shoot Lapua brass, because of its superior quality and uniformity, not to mention lower cost. The case capacity of Lapua brass is about 38-39.5 grains of H20, after fire-forming. The exact capacity depends on your gun’s chamber and the brass lot.

It would seem you have the shorter chamber but a chamber cast would verify it.

There are no SAAMI specifications for any of the BR family.

 

[xpilot]

Any problem just trimming to the shorter length??????????

 

[hogpatrol]

From the 6br page:

The 6mm BR that is most commonly used today is also called 6mm Norma BR, “6BR Norma”, or just plain “6BR”. Norma started with the 6mm Remington Benchrest and increased the base dimension slightly. But the official SAMMI cartridge OAL is the same: 1.560″. (However Remington did originally produce brass at 1.520″ OAL and some older chambers have been cut to a shorter length.) Though Norma standardized the round, most people shoot Lapua brass, because of its superior quality and uniformity, not to mention lower cost. The case capacity of Lapua brass is about 38-39.5 grains of H20, after fire-forming. The exact capacity depends on your gun’s chamber and the brass lot.

It would seem you have the shorter chamber but a chamber cast would verify it.

There are no SAAMI specifications for any of the BR family.

Cartridge dimensions, chamber dimensions or max average pressure? Or all three?

 

[CatShooter]

From the 6br page:

The 6mm BR that is most commonly used today is also called 6mm Norma BR, “6BR Norma”, or just plain “6BR”. Norma started with the 6mm Remington Benchrest and increased the base dimension slightly. But the official SAMMI cartridge OAL is the same: 1.560″. (However Remington did originally produce brass at 1.520″ OAL and some older chambers have been cut to a shorter length.) Though Norma standardized the round, most people shoot Lapua brass, because of its superior quality and uniformity, not to mention lower cost. The case capacity of Lapua brass is about 38-39.5 grains of H20, after fire-forming. The exact capacity depends on your gun’s chamber and the brass lot.

It would seem you have the shorter chamber but a chamber cast would verify it.

There are no SAAMI specifications for any of the BR family.

Cartridge dimensions, chamber dimensions or max average pressure? Or all three?

None of the three...

When it was introduced back in '92 (??), Remington never intended for the BR family of cartridges to be factory cartridges (in the normal sense of the word).

I had one of the first 7mmBR's made and what a friggin' nightmare it was to make cases for it.

The BR family has had so many permutations and variants, that at this point SAAMI would not consider accepting it.

The average pressure that shooters are using is probably around 65Kpsia.

 

[xpilot]

What are the pros & cons of just trimming to length?

 

[hogpatrol]

None of the three...

"When it was introduced back in '92 (??), Remington never intended for the BR family of cartridges to be factory cartridges (in the normal sense of the word).

I had one of the first 7mmBR's made and what a friggin' nightmare it was to make cases for it.

The BR family has had so many permutations and variants, that at this point SAAMI would not consider accepting it.

The average pressure that shooters are using is probably around 65Kpsia."


That makes sense. With all the iterations of it, it's a good thing it's an easy one to tune for excellent accuracy. Thanks for the info and obviously there are a few factual errors on the main 6BR info page. Hog

 

[xpilot]

What are the pros & cons of just trimming to length?

Any problems?