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jo191145
12-27-2007, 07:38 PM
I'm looking for some advice on a 6BR barrel I'm going to be ordering for a Savage target action build (my first).
Going with a Shilen screw on I see the standard chamber options as
6mmBR Norma .272 neck or
6mmBR .270 neck.

I wouldn't mind turning the necks a little for the .270 neck but what other difference would there be in the chambers?
I'm planning on using over the counter Redding dies. Anyone care to guess which chamber would most closely match the I.D. of those dies assuming there is a difference.

My other choice was a Lothar Walther. I inquired about neck sizes and they said they would use a standard large reamer. No specs given. Anyone care to guess what neck size that may be? Chamber dimensions?

I've settled on a 26 inch 8 twist (I think). No plans for going past 600yds at this time but I always like to leave my options open. If I'm given the option (not likely) how much freebore should I request? I think I read .060 is a good number for a wide range of bullet weights.

What am I missing?

Its becoming readily apparent why you guys have your own reamers;)
Sorry for the dumb questions:o

jackie schmidt
12-27-2007, 09:35 PM
Go with a .272 neck if you do not want to turn necks. The .270 will be a little tight, in my opinion. The .272 will allow you to use just about every bullet, even the BIB 95 grn FB that has a pretty big gas ring compareed to most of the big boat tails.
If you go with a .270, there will be very little to turn if you decide to go that route. I use a .269.
Any Gunsmith worth his lathe turnings knows that you should use a reamer ground to accept Lapua Brass. Don't even consider using any other brand. The Lapua is that good. Lothar's statement "standard large reamer" doesn't instill confidence.
The freebore?? If you go with a .060, that will limit you to just one 105+ GRN offerring, that being the Berger 105 VLD. A .O60 will put the straight part of the shank, just at the boat tail, about .090 above the neck shoulder junction. If you use the regular Berger Match, or the Sierra 107, you really need a .100 freebore, maybe a tad longer. If you decide to shoot some of the BIB 95's or bigger, you definetally will need the longer freebore.
Of course, the longer freebore will limit you on how light, (short) of a bullet you can use.
I have a friend that used my .060 throat .269 neck reamer in his 1-8 twist 6BR, (.236 4-groove Krieger Barrel), and it shoots the 105 Berger VLD and the Lapua 107 Scenar great......jackie

alinwa
12-28-2007, 03:00 AM
Jackie's pretty well nailed it here but I'll chime in with a couple observations anyway. :)

I have a reamer with .270nk that's been used on 7 barrels and I've never had to actually turn any brass for them but there are two factors that I need to clarify. Number one, I'm still using a batch of 1000 Lapua cases that I bought back in '98. THIS LOT of brass loads at .2685 to .2695 with the bullets that I've used in these barrels. I mainly set this reamer up as a no-turn for use with VLD's and it's worked well as such. I've used several lots of Bruno, Berger and Euber 68gr FB Match bullets and never yet ran into a problem with the pressure ring.............BUT!!!!!


This is the big kicker.........I have a piece of barrel stub that I call a "gizzie" and I run EVERY loaded piece of new fireform brass into it to check for binding. OR, on those rifles where one can feel the round seat ALL THE WAY when singly loading I will carefully check or gauge the brass in the rifle itself.........BUT!!!!

:)


If you feel any binding you must stop and check it out.


I've ran all the way to "scuff-fit" in several chamberings with no ill effects except that when using flat-based bullets it seems that running this tight may produce fliers. Some really top shooters (which I'm NOT) will tell you as a fact that running less than .002 clearance with FB bullets is a mistake. I primarily use boattail bullets, VLD's, in my BR's and I find no tendency toward fliers when using very tight tolerance with these.

IMO Jackie's spot on with his suggestion of .272, using .270 is really pushing it.


I also agree totally with his assessment of freebore.

I will go further though and suggest that you simply steer clear of the whole Lother Walther thing, reamer and barrel.


BTW "guessing" about reamer spec's is something I'll not do!! I've been burnt too often. I own and KNOW my own reamers.


al

vlcakc
12-28-2007, 11:31 AM
Remember, the Savage target action uses the large barrel shank. Several months ago I inquired about a Walther barrel for my Savage and was told that the large barrel shank would be a "special" at a several hundred dollar premium over the small shank prefit barrel. This pricing may have changed since then, but should be checked out to make sure. Vic

jo191145
12-28-2007, 05:05 PM
Thanks guys for your help. I'll go with the .272 Norma chamber. I will call Shilen again and dig a little deeper into the differences in chambers.
Lapua is a given. Pretty hard to believe they offer three 6BR chambers designed for Rem brass and just one Norma spec chamber. Maybe I'm missing something.

One clarification to my original post. Most of my shooting occurs at 200-300yds. What can I say I live in a small congested state.:D
Would your freebore recommendations still stand knowing this new info? Any recommendations on bullet weight that performs the best at these distances? I'm thinking a medium weight flatbase should suffice, perhaps even be best.

I would also like to throw a new question out there. Ratchet Rifling? Shilen offers thier 8 twist in either Ratchett Rifling or a "Special for VLD over 100gns"
Any opinions on Ratchet Rifling?
Not sure what would be "special" about a VLD rifling unless they're referring to a longer freebore.

Thanks again for your insight.

LW barrel in large shank (not standard) with 8 twist (not standard) would be $410.00 shipped.
From all accounts LW makes a real fine barrel. I would have liked specs and not generalities though. I should have pressed both companys harder for real numbers and info. I will now.
I might still order the LW tube because it will arrive much sooner. Simply change my Shilen order to a .20BR. Thats next on the list.