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BR case neck thickness?

Redfoot Ranch

Sergeant of the Hide
Full Member
Minuteman
Apr 16, 2018
181
28
Mid MI
Good morning,


I am looking to start spec'ing a reamer for a 6 BR variant and have not yet been able to get my hand on brass to measure. Through site searches here I have found posts with mic'd thickness from over 10 years ago Blue/Brown box Lapua. What I am asking for here is some more recent measurements based on the following for Lapua, Alpha and Peterson brass measured with a tube or ball micrometer:


Brand of brass?
Lot number?
Smallest and largest thickness found in your sample?


Please, and thank you, Dale
 
Just go with the 6mmBR "No turn neck" reamer and not have to worry about neck thickness. I am glad I was talked into that option when I was asking about reamer choices. Unless you were planning on turning all your necks.
 
Do you want to turn necks? Do you plan to buy 6br brass or resize some other brass to your variant?
 
I have half a dozen lots of blue box BR brass that’s all been blown into BRA and fired a few times, at least. I can measure it if you like though. The dudes over at accurateshooter might have a ready answer with less nonsense than here.
 
Brand of brass?
Lot number?
Smallest and largest thickness found in your sample?

The dudes over at accurateshooter might have a ready answer with less nonsense than here.
I guess our answers are nonsense considering there are a couple of choices in "tight neck" reamers .269"-.265", although the general consensus at Accurateshooter is to choose the "No-turn" neck at .272" to avoid the necessity of uniforming your brass. I don't shoot Alpha or Peterson, but Lapua apparently has some variation in thickness over the years. Thus giving the OP a number of what you have may be irrelevant to what brass he can currently get (or wait for).
 
I’m a fan of a .272 neck for unturned Lapua. And .269 has worked very well for me as a “tight neck” configuration with Lapua brass.

But since you asked: Lapua unturned, blue box, from at least 4 different lots (that’s all the boxes I could find, I’m sure I threw some away) purchased at intervals across the last five years or so. I’m too lazy to copy down these lot numbers. If it’s important to you, pm me.

All measured .0115” to .012”

Brand new Alpha 6BRA brass ALSO measured .012”.

Brand new Peterson 6Dasher brass measured .012” as well. Not exactly the same but close enough to be representative, I believe.


I guess our answers are nonsense
You haven’t answered his question yet and that’s exactly the nonsense I’m referring to.
 
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Just go with the 6mmBR "No turn neck" reamer and not have to worry about neck thickness. I am glad I was talked into that option when I was asking about reamer choices. Unless you were planning on turning all your necks.
I have a couple dozen BR/BRA reamer drawings on hand from PT&G, JGS and Manson. The neck diameter's spec'd on the "no turn neck" specific drawings in have vary from .2705 - .274. I would like to be more specific than this! I prefer a no turn as my final step before seating a bullet is an expander mandrel but I am set up for turning necks if necessary.

I appreciate your response. Are you able to provide any specific input based on the OP?

Thanks, Dale
 
Do you want to turn necks? Do you plan to buy 6br brass or resize some other brass to your variant?
I appreciate your response but I don't see the relevancy to my OP. To answer your questions - not necessarily and 6BR. Are you able to provide any specific input data based on the OP?
 
I have half a dozen lots of blue box BR brass that’s all been blown into BRA and fired a few times, at least. I can measure it if you like though. The dudes over at accurateshooter might have a ready answer with less nonsense than here.
Yes, please and thank you.
 
I guess our answers are nonsense considering there are a couple of choices in "tight neck" reamers .269"-.265", although the general consensus at Accurateshooter is to choose the "No-turn" neck at .272" to avoid the necessity of uniforming your brass. I don't shoot Alpha or Peterson, but Lapua apparently has some variation in thickness over the years. Thus giving the OP a number of what you have may be irrelevant to what brass he can currently get (or wait for).
From my experience, all brass within a specific box has thickness variation. In the past when neck sizing strictly by means of a bushing, I neck turned everything to uniform my brass and all was done for NT chambers. Since going to expander mandrels to control my "neck tension", and for what I feel is better concentricity, I am not turning necks. To work brass minimally I still bush down but only far enough for the appropriate mandrel to do it's job - based on whether I am looking for .005 to 5 thou of neck interference.
 
I’m a fan of a .272 neck for unturned Lapua. And .269 has worked very well for me as a “tight neck” configuration with Lapua brass.

But since you asked: Lapua unturned, blue box, from at least 4 different lots (that’s all the boxes I could find, I’m sure I threw some away) purchased at intervals across the last five years or so. I’m too lazy to copy down these lot numbers. If it’s important to you, pm me.

All measured .0115” to .012”

Brand new Alpha 6BRA brass ALSO measured .012”.
Thank you! Are these numbers from virgin, un-fired brass and in addition to the fired cases you mentioned in a previous post?
 
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Thanks you! Are these numbers from virgin, un-fired brass and in addition to the fired cases you mentioned in a previous post?
Unfortunately all the Lapua has been fired at least a couple times. I don’t have any Virgen brass at the moment. The lot that I neck turned for a .269 barrel measures .011”. I used to write down neck wall on the new brass before I did anything with it. I’ll look in the books and see if I have those numbers.

The alpha is new and I measured a handful of pieces. All exactly .012”.

I just happened to have the new piece of Peterson sitting on my bench. I borrowed it as a measuring reference….my money says their BR brass would be the same.
 
Unfortunately all the Lapua has been fired at least a couple times. I don’t have any Virgen brass at the moment. The lot that I neck turned for a .269 barrel measures .011”. I used to write down neck wall on the new brass before I did anything with it. I’ll look in the books and see if I have those numbers.

The alpha is new and I measured a handful of pieces. All exactly .012”.

I just happened to have the new piece of Peterson sitting on my bench. I borrowed it as a measuring reference….my money says their BR brass would be the same.
I look forward to those virgin Lapua numbers if you find them. Thanks, again!
 
I appreciate your response but I don't see the relevancy to my OP. To answer your questions - not necessarily and 6BR. Are you able to provide any specific input data based on the OP?
The combination of statements and your request seemed odd to me. You are spec'ing a reamer. You want to know the neck thickness of commercial brass. Your reamer guy can make the reamer neck anything you ask for - SAAMI or something else. I have everything from tight-neck BR guns, custom chambers to my spec, commercial chambers, and military chambers. I wanted to understand what you were doing so I could put your note in context and then maybe I could say something useful. Enjoy.
 
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The combination of statements and your request seemed odd to me. You are spec'ing a reamer. You want to know the neck thickness of commercial brass. Your reamer guy can make the reamer neck anything you ask for - SAAMI or something else. I have everything from tight-neck BR guns, custom chambers to my spec, commercial chambers, and military chambers. I wanted to understand what you were doing so I could put your note in context and then maybe I could say something useful. Enjoy.
I just got frustrated when questioned about my intent and no answers regarding my questions asked. Going forward, perhaps simplifying this with bold indicating anything added...
Good morning,


I am looking to start spec'ing a reamer for a 6 BR variant and have not yet been able to get my hand on brass to measure. Through site searches here I have found posts with mic'd thickness from over 10 years ago Blue/Brown box Lapua. What I am asking for here is some more recent measurements based on the following I am looking the neck wall thick for Lapua, Alpha and Peterson BR or BRA virgin brass measured with a tube or ball micrometer. Please respond with:


Brand of brass?
Lot number?
Smallest and largest thickness found in your sample?


Please, and thank you, Dale
...will return a simple 3 part response, like I have gotten with the same OP on other forums? I'm sorry for any misunderstand on my part here. I didn't realize the online forums had become like most social media - where it appears that most people want to be an "influencer" based on intent.

Thanks y'all, Dale
 
Every thread on here is a knockdown drag out fight full of political misinformation, poorly educated grammar and punctuation, desperately held opinions about unrelated topics and basic ignorance being paraded as scholarship. Good luck with any question about anything. Don’t believe anyone or anything until you verify it somewhere else.
 
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I received 100 pieces of Alpha 6BRA brass, Friday of last week, which I have necked 1 piece down to 22 cal so I could compare dimension and case capacity of both. I have read that their BRA brass is shorter than "normal" headspace length by .009". I have recorded the length using a 28 cal Hornady bullet comparator, which is the smallest I have that is larger than the neck OD. Alpha is sending me 6BR samples to use for comparing the dimension and case volume against their BRA brass. I will compare it's length with the comparator - bearing in mind the 10 degree shoulder angle difference.

I just picked up 100 pieces of Peterson and they are now inbound.

Once I find Lapua available, as well as with the inputs I have received from others, I will then have what I need for reamer spec'ing and to build Norma-based chamber models for the 22 BR, 22 BRA and 6 BRA in QuickLoad. I can then compare these against the 22x47L & 6x47L models (which I have built in QL) to see which I will build next to compliment/replace the 22 and 6 Creedmoor's I currently run.

Thanks to all for their input! As they say, "You can always learn something, even if it's what you don't want to do."