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Sizing New Brass

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04 April 2007, 23:06
Wooly ESS
Sizing New Brass
How is new, unfired brass sized? Has it be manaufactured to the same specs as factory ammo? In other words, can new brass be loaded without running the case through the sizing die, or should it be sized like any other cartridge case before it is loaded?


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but first it's gonna piss you off!
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04 April 2007, 23:22
ned
Theoretically it's made to minimum spec sizes for the caliber. However, often you will find many with less than round necks in a lot of 100. To make sure all the necks are uniform and to avoid any unpleasant surprises, I always full lenght size my new brass. I'm sure others do it differently, but I feel comfortable with this approach so I do it.


it's a fresh wind that ... Blows Against the Empire
04 April 2007, 23:37
fredj338
I'm w/ Ned on this too, run them through your FL die, chamfer the case mouths & check to make sure they are all the same length.


LIFE IS NOT A SPECTATOR'S SPORT!
05 April 2007, 01:02
Dwight
To do it without worrying with lube just run it up til you feel the expander slide in the mouth and then a little more for the neck to hit the sizer. This is all that I do just to get the mouth round. Chamfer and load and have fun.
05 April 2007, 06:24
kraky
I've been buying the federal primed brass from Natchez and just love it. It's cheaper than Rem or Win and seems to hold up just fine. Unfortunately they are out right now of most popular calibers. It's possible that with the war going on Federal has got contracts to fill.

Anyhow I got out a bag of 300 win that I bought earlier in the year. Just ran them over my lyman M die to size the case mouths, did an inside mouth chamfer, loaded, and seated the bullets. I don't think there was a one with over .003" runnout.... most were at .002.
That's neat when that happens. They were selling that primed brass for $16.50/ 50 cases earlier this year. I hope they have more later and that good of a price.
05 April 2007, 18:52
stillbeeman
Unless you've some sort of custom cut chamber, you should be able to bump the resizing ball thru the neck to make sure it's round, chamfer the inside of the neck and load 'em up and shoot 'em.
Just to be anal, you can drop a couple into your chamber to make sure they chamber readidly.
05 April 2007, 23:29
DM
quote:
Unless you've some sort of custom cut chamber, you should be able to bump the resizing ball thru the neck to make sure it's round, chamfer the inside of the neck and load 'em up and shoot 'em.

I agree, and it's exactly what i've been doing for more than 30 years now...

DM
06 April 2007, 01:18
Buliwyf
In my experience in gerneral, new brass is sized to minimum SAMMI specs. A lot of the time running the brass neck over an expanding mandrel and chamfering helps the first load. However, my experience with Nosler Custom brass has been good.
06 April 2007, 01:18
temmi
What can I say… I FL Size all brass to round out the necks and then I do a full prep job…

Trim to uniform Length
Uniform Primer pockets
Uniform Neck
Deburr & Chamfer
Deburr Flash hole

At the very least you should
Trim to uniform Length
Deburr & Chamfer
Deburr Flash hole

Heck it is a hobby, have fun… be safe
06 April 2007, 19:10
stillbeeman
I think you'll find that if you trim to uniform length before the first firing, after you've fire formed the brass, the length will be out of kelter again. So why bother until the brass is 1X.

It is indeed a hobby and to me, most of the fun is found on the firing line, not in the shop. But, like the fellow that kissed the cow......... Big Grin
07 April 2007, 13:35
Warrior
Case preparation start on day 1 when you get your brass.

1) Inspect them and cull them:

Inspect them and cull the odd ones, if present.
I have seen some cases that are way too short.
Benchrest shooters weigh them and classify them.
It makes no sense to measure powder charges to a 1/10 th decimal
and then case volumes generally differ from 1 to 2 grains.

Example: I weighed 10 Winchester 300 H&H cases:
The extreme spread was 4.8 grains - Lowest 240 grains, Highest 244.8
The average being 243.5 grains with a standard deviation of 1.8

2) Dolly them up:

FL size them and the expander ball will uniform all neck sizes.
Then trim them all to the same length, within spec.
Chamfer the inside of the neck & and then outside.
That will make bullet seating smoother as it engages the neck.
Check primer pockets to have the same depth (for even ignition).
Debur the flasholes to make them all uniform (for even ignition).
Benchrest shooters will uniform neck wall thickness as well for
an even release of the bullet.

3) Case prep takes up most of the time if you do it right.

When you buy a batch of 200 cases, then you do them all at once
and put them away save for the batch that is going to be in use.
I only keep 20 cases in use at all times and record the number of
firings so I can retire them all at once when the time comes.

Since reloading is a hobby to custom make your ammo, you may as well do a bit more than what the factory is doing. The objective being that you want better accuracy out of your rifle.

Warrior