Neck thickness with Lapua brass?

K

kyreloader

Guest
Long post.

I have a 284 Shehane reamer and a Shilen barrel on order. The reamer has a .313 neck, so what neck thickness should I turn my brass. Doess the common recommendation of 0.002" (on each side) clearance hold with the Shehane?


I plan on using 180g Bergers(which measure 0.287 in diameter).

.287 + (0.011x2)= .309 -- does that sound right?
 
Are you sure about the diameter of the bullet? I do not think they are .287" You might want to check your measuring tool for accuracy.
 
Is 0.0125 enough or sufficient neck thickness?

Is 0.004 enough "slop" when loading?
 
Loaded Neck for a 284 Shehane

I have a 0.313 Chamber Neck in mine and I run a 0.310 loaded neck. I have also run a 0.311 and don't see a noticable difference. I am thinking of trying a 0.309. The turned neck walls on my Lapua brass are about 0.0127 inches per side measured with a Hollands Neck Thickness Micrometer to end up with a loaded neck of 0.310 with Berger 180 VLDs. The math doesn't add up that way, but there it is.
 
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Without regards

to the thickness of the brass and the dia of the bullet............it will be the measurement of the loaded round that counts.

Are you using a micrometer or calipers?

Hard to believe the Bergers are .287.
 
Loaded Neck Diameter 284

JohnS
If I add 0.0127 + 0.0127+ 0.2840, I get 0.3094 inches; however when I measure the same necks loaded with an outside micrometer which reads to 0.0001 inches, they turn out to be 0.310 inches within a ten thousandths or so. I think the small difference is measurement error of the neck walls due to uneven surfaces on the inside of the neckwalls. The Bergers may be a bit over 0.284 inches, but I have never bothered to measure them that way.
 
You are going to have big problems trying to shoot .310 loaded rounds
in a .309 neck chamber. I would suggest you take your bullets and
measuring tools to a trained person for advise.
 
284 Shehane Necks

Bob.
I'm a little confused. I can't find any reference to a 0.309 inch chamber neck in this thread, just 0.313 inches as far as I can see.
 
TonyR said:
I have a 0.313 Chamber Neck in mine and I run a 0.310 loaded neck. I have also run a 0.311 and don't see a noticable difference. I am thinking of trying a 0.309. The turned neck walls on my Lapua brass are about 0.0127 inches per side measured with a Hollands Neck Thickness Micrometer to end up with a loaded neck of 0.310 with Berger 180 VLDs. The math doesn't add up that way, but there it is.
Click to expand...

3rd line down
 
Just to be clear, the 0.311, 0.310, and 0.309 inches are cartridge loaded neck diameters I have either tried or intend to try in my 0.313 inch neck chamber. Sorry for any confusion.
 
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