Chambering 6br go/no-go depth?

Z

zini72

Guest
My gunsmith is currently chambering a new rifle for me.
It is a 6br using his reamer w/.269 neck. He told me that it is a little on the "tight" side, meaning I will have to full length size & neck turn all of my brass to get it to chamber.
The neck turning part is what I wanted, but the tight chamber and having to use small base dies had me a little concerned. Any one have an opinion on this?
Thanks,
Edward
 
zini72 said:
My gunsmith is currently chambering a new rifle for me.
It is a 6br using his reamer w/.269 neck. He told me that it is a little on the "tight" side, meaning I will have to full length size & neck turn all of my brass to get it to chamber.
The neck turning part is what I wanted, but the tight chamber and having to use small base dies had me a little concerned. Any one have an opinion on this?
Thanks,
Edward
Click to expand...

It'll klik

you'll hate it
 
alinwa, thanks for your thought. I hate clicking, that is usually when I throw brass away?!
This rifle build is with a BAT MB action set in an ST1000 stock and 28" barrel. Primary use of 600 yd br. using a berger 105?
Will running the reamer in deeper solve the clicking problem?
Thanks again,
Edward
 
I agree with Al, it isn't a headspace issue, it's a diameter issue at the rear of the case...

Overly tight diameters are nothing but a problem and of no advantage over a correctly sized chamber.
 
Due to differences in equipmet, set up and technique, would it be possible for two different gunsmiths to produce a tight chamber and a spec chamber from the same reamer? - nhk
 
The gunsmith may have only been referring to the neck dimension of the chamber. Ask him for a reamer drawing. You may be worried for nothing. If I were having a rifle built, or a barrel chambered, I would want to know the actual dimensions of the reamer being used so that I could make a determination as to its suitability. Chamber dimensions would be one of the last places that I would want to compromise a project, and if that meant that I needed to buy a reamer to get what I wanted, I would not hesitate. Rereading you post, one more comment...new brass should never need sizing to fit a chamber of the same caliber. Of course turning the necks is another matter.
 
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muldoon9 said:
Al-
Whats a "klick" ?

Michael
Click to expand...

When you fire hot loads in something like a BR case (which is what it's designed for) the brass swells up just a little at the base. Not enough to loosen the primer pocket but enough that it gets tight in the base of the chamber if your chamber is too tight, too small to allow for the expansion. You sizer die can't help you so you have tight extraction, the action of the primary extraction cam at the top of the opening stroke will pop the case loose but only with a "click."

Or "klick" in metric

al
 
In the case of the BR there are dies that can handle this. Redding's small base, and Harrell has a die that will size for any chamber. If it were a different case, (other than a PPC) life wouldn't be as easy.
 
Wayne Shaw said:
In the case of the BR there are dies that can handle this. Redding's small base, and Harrell has a die that will size for any chamber. If it were a different case, (other than a PPC) life wouldn't be as easy.
Click to expand...

Ditto on Wayne's comments. If you haven't bought any dies yet, just send a couple fired cases to Harrell's and they'll match a die to your fired cases. I have found it useful to go with the next die down in size from their recommendations, though...a 2.5 if a 2.0 is recommended, for example.

Everyone looks at the back of these BR cases for 'click' issues. Many times it's the shoulder dia. that needs tweaking.

Good shootin'. -Al
 
I don't think he meant tight as diameter, I would think he meant tight regarding length. You can't cut smaller than the reamer but you can cut larger. In fact, we have many posts about reamer holders that ensure straight and properly sized chambers not over sized chambers.
 
zini72 said:
He told me that it is a little on the "tight" side, meaning I will have to full length size & neck turn all of my brass to get it to chamber.
The neck turning part is what I wanted, but the tight chamber and having to use small base dies had me a little concerned. Any one have an opinion on this?
Thanks,
Edward
Click to expand...
First, get him to explain what he means by tight, then g from there, all else is just second-guessing.
 
nhk

"Due to differences in equipmet, set up and technique, would it be possible for two different gunsmiths to produce a tight chamber and a spec chamber from the same reamer? - nhk"



There has been much good info posted here on how to ream chambers to "exactly" reamer diameter by
pre-boring and using a reamer pusher----as opposed to a reamer holder which could possibly ream to an oversize diameter.

With these methods, a high level of chamber diameter uniformity can be achieved and the chamber
"tightness" is determined by the reamer dimensions.

In my opinion, two different smiths, using the same reamer, with two different methods could ream different sized chambers.

The methods posted here are good------they work.

A. Weldy
 
Wayne Shaw said:
In the case of the BR there are dies that can handle this. Redding's small base, and Harrell has a die that will size for any chamber. If it were a different case, (other than a PPC) life wouldn't be as easy.
Click to expand...

Not true.

While this was also proposed by the 'smith in the Original Post it doesn't always work. It took me 5 different 6BR reamers and about 8 dies to get this sorted.

al
 
Lucky Shooter A said:
"Due to differences in equipmet, set up and technique, would it be possible for two different gunsmiths to produce a tight chamber and a spec chamber from the same reamer? - nhk"



There has been much good info posted here on how to ream chambers to "exactly" reamer diameter by
pre-boring and using a reamer pusher----as opposed to a reamer holder which could possibly ream to an oversize diameter.

With these methods, a high level of chamber diameter uniformity can be achieved and the chamber
"tightness" is determined by the reamer dimensions.

In my opinion, two different smiths, using the same reamer, with two different methods could ream different sized chambers.

The methods posted here are good------they work.

A. Weldy
Click to expand...


Could also mention that whether or not gunsmith is using a constant chamber reamer flushing system will also influence chamber size/dimensions. A cooler (temperature) reamer and better surface finish that requires less polishing/finishing will result in a tighter spec and more dimensionally accurate chamber, with less chance of rings or gouge marks - especially if it is in a stainless barrel.

Over polishing, or a poor technique (or machine setup) can also create oversized chambers (in relation to the reamer specs).

Cheers,

D.
 
alinwa said:
Not true.

While this was also proposed by the 'smith in the Original Post it doesn't always work. It took me 5 different 6BR reamers and about 8 dies to get this sorted.

al
Click to expand...

Not true.

This isn't a rocket science. With the 30BR being so popular now, dealing with BR brass is not hard to do. Mr. Nyhus is right, the shoulder can be an issue sometimes. A Redding die probably sizes the shoulder a bit too much. My 30BR die was done by Jim Carstensen, and he used a small base die as the basis and worked from there. Harrell's dies work well.
 
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