Lapua 6BR Blue Box Brass Loaded Neck Diameter

[Boatschool02]

Lot # 2714015
Bullet: Berger 95VLD-Hunting
Loaded rounds range from 0.2694 to 0.2701
Unfired, 0.2425 expander mandrel processed thickness ranging from 0.0125 to 0.0135
Gunsmith ordered a 0.2720 reamer (despite prevailing trend toward 0.2705 for "no turn")
-
I don't mind a minor clean up. However, I do encourage others with the smaller "no turn" neck diameter to measure new brass vice assuming sufficient clearance.

 

[Cool Tool]

Lot # 2714015
Bullet: Berger 95VLD-Hunting
Loaded rounds range from 0.2694 to 0.2701
Unfired, 0.2425 expander mandrel processed thickness ranging from 0.0125 to 0.0135
Gunsmith ordered a 0.2720 reamer (despite prevailing trend toward 0.2705 for "no turn")
-
I don't mind a minor clean up. However, I do encourage others with the smaller "no turn" neck diameter to measure new brass vice assuming sufficient clearance.

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That 3rd set of mikes I really like.

 

[HTSmith]

That is consistent with what I found with my blue box brass--though my measuring tools aren't as sophisticated. I've had good results with a .271 and a .272 neck chamber. I'm more comfortable with the .272.

 

[shoot4fun]

What you are seeing, according to what I hear from a friend who was working on some new lots, this is widespread and not just isolated to one lot of brass.
I know many a reloader who say they "know" Lapua brass is so good they don't even check it. Maybe they should.

 

[pat fulghum]

Use .272 reamer or give them a quick spin the neck lathe....

My loaded rounds are .2695... so .2705 is too tight in my opinion...

Boatschool02, What is the make/model of the 3rd mic... the neck micrometer.

Remember that my opinion, like most others on this forum, does come with a 100% money back guarantee.

 

[Boatschool02]

Mitutoyo 115-313. $119 on Prime.

 

[pat fulghum]

Boatschool02. Thanks ... ordered

 

[lloydx2]

There is a 6br reamer with neck @ .470.8 that several guys have been using for high power prone.
The newer blue box has thicker necks than the original lots. I hope they are reading this thread.

 

[AndyTaber]

I have two 6BR's, a 14 twist and an 8. The necks on both are .2704 and i dont do any neck turning. Between them i have over three thousand rounds fired and never had a problem. I have loaned my reamers to several friends that I shoot with and have no problems reported. Your mileage may vary.

 

[HTSmith]

There is a 6br reamer with neck @ .470.8 that several guys have been using for high power prone.
The newer blue box has thicker necks than the original lots. I hope they are reading this thread.

My Blue box necks are a tad thinner than my old cardboard box.

 

[lloydx2]

I am talking about guys that are putting 90-100 down before cleaning
(high power) Any one that runs under .002 neck clearance doing this will learn the hard way.

 

[pat fulghum]

Lloyd,
What happens?
I rather learn by reading than doing

 

[lloydx2]

Pressure. If you are planning to shoot F class or prone sling.
Go with at least .003 Better would be .004.