.30 BR Help

[6mmHot]

I need you help please guys.
A couple of us are thinking of building some .30BR's
We are in the process of ordering a batch of tubes from Bartlein.
We are wondering what sort of rifling is best a 4 grove or a 5R type rifling?
From this site an 18 twist seems to have an accuracy edge but no mention really on rifling.
So do any of you guys shoot one any of your thoughts or tips would be great.
Cheers
Dave

 

[6mmHot]

Thanks for the most useful replies guys.
By the way what contours and barrel length are you using.
Was thinking down a LV or modified LV line?
Cheers
Dave

 

[JRS]

The twist will depend on the bullet weight and ogive. 7 ogive? 10 ogive? 112gr? 118gr? etc, etc.

 

[Eddie Harren]

I use Lilja 3 groove, 17 twist barrels with the 110 Gr. 7 Ogive bullets made on .925 jackets.

 

[eww1350]

Dave, I have both a 5R Bartlein and a four groove Krieger, both 1 in 17" 30 BR. I don't see any advantage of one over the other.

The 30 BR is easy to clean to start with so the "stuff in the corner" issue is moot. The same load shoots at the same velocity in both. Accuracy is so good that it's always a matter of "the gun was pointed the wrong way" as far as scores go.

I faced the same decision you're looking at and ordered a new Krieger 4 groove, mostly because Bartlein's lead time was so long and I'm not gettin' any younger. I didn't wear the others out but want to try a new reamer with an OAL of 1.560" without giving up one. Trying to take advantage of the additional length gained from fireforming brass rather than using expanders.

Rich...I have one of the new PTG 1.560" (Jackie Schmidt) reamers...be aware that when fireforming the new Lapua 6br brass it will not cleanup at .010" (more like.009")wall thickness..maybe if you find some older mfg. Lapua brass it might cleanup at .010"...mine would not...it came in the new blue box...

 

[Eddie Harren]

Rich, I'm curious as to why you need to trim .050" off of the brass.

 

[Eddie Harren]

I've been using Lapua 6BR brass to form 30BR for about 4 years. I trim to 1.500". I have never had this brass get to 1.555". I can always tell when my brass gets a little long, like at 1.520", the bolt gets a little hard to close and the shot will always go 1 ring high.

 

[6mmHot]

Thanks guys for the help.
An order has been placed for a couple of Mod HV profile barrels with a 1 in 17 twist and 4 groove rifling.
No the wait for them to arrive and then the fun will start.
Cheers
Dave