Using New Brass

Muntjac

Well-Known Member
When using new brass should you run it through your full length resizing die and trim all to the same length?
 
Yes. This is essential. New brass can be very irregular, so a FL check with a vernier is standard practice.
 
new brass

hi,

I just loaded some new lapua brass this week end just gone, all I did before loading it was push it gentle into my neck sizing die to ensure the case mouth was perfectly round.

It shot the best groups the rifle has ever achieved.

If its new from the factory it should be in the correct tolerances.
 
If its new from the factory it should be in the correct tolerances.

Absolutely NOT true. The operative word you used was "Should". Every loading book you can buy will tell you strictly not to do this. All brass must be checked, this is NOT to say that it will all need sized. All factories have tollerances, which means exactly that, it's NOT all the same size, but rather should be within tollerance, which MAY not match the rifle.

You were simply lucky in this situation.

No one should take advice from the general public online (including me!) when reloading. Read books written by ballistics professionals, like THIS one.
 
That being said, Lapua brass is extremely expensive, you are paying for accuracy in manufacture. However, the fact remains that it MUST be checked. Not checking is almost as silly as assuming that each powder measure is bang-on; you just don't do it. We're dealing with explosions here, not sharpening a pencil.
 
It would depend on the type of shooting you are into ,

You need to do a quality control,

The new cases are a product that are made to a tolerance like the chamber in the rifle ,
For first time firing , check that the condition of the cases are free from dents ,
check the mouth of the case for burrs and a small champher into the case ,
check the primer pocket is clean and square ,
you could ream the gas hole through into the body of the case .
When you fire the new case they will take the tolerance of your chamber this fire forming , then as you reload you will check the length of the cases and trim to length , and when the case dimension changes and it becomes tight on closing the bolt you would then use you dies to return the cases to a prediturmind dimension .

ATB
 
Thanks Lee303 and ATB, I think I will put them throught the sizing die and trim just as with fired case.
 
NP Muntjac, only too glad to be of help.

Although the contrary may seem evident, I am not sponsered by the writers of THIS book, nor am I Richard Lee himself, and I do realise that I keep preaching on about THIS book in various threads throughout this forum, but I really can't recommend it enough.

One final word I will say, is that if you intend to use the brass in the same rifle everytime, I would avoid full length trimming too often. The brass will 'fire form' to the rifle chamber in question, and will usually only require neck sizing after the initial full length check/trim of the new brass. Full length trimming everytime will result in massive brass flow, causing work-hardening which will lead to extremely brittle cases that could split easily and will certainly not last half as long as they should.
 
NP Muntjac, only too glad to be of help.

Although the contrary may seem evident, I am not sponsered by the writers of THIS book, nor am I Richard Lee himself, and I do realise that I keep preaching on about THIS book in various threads throughout this forum, but I really can't recommend it enough.

One final word I will say, is that if you intend to use the brass in the same rifle everytime, I would avoid full length trimming too often. The brass will 'fire form' to the rifle chamber in question, and will usually only require neck sizing after the initial full length check/trim of the new brass. Full length trimming everytime will result in massive brass flow, causing work-hardening which will lead to extremely brittle cases that could split easily and will certainly not last half as long as they should.
On the contrary, all fired cases need to be checked for full length dimensions, the above post was I am fairly sure meant that full length SIZING was not required, just neck sizing, if you have a soft case that flows forward on first firing, & you reload the case without a length check, you could end up trying to chamber something that is too long!.
 
On the contrary, all fired cases need to be checked for full length dimensions, the above post was I am fairly sure meant that full length SIZING was not required, just neck sizing, if you have a soft case that flows forward on first firing, & you reload the case without a length check, you could end up trying to chamber something that is too long!.

I do not wish to initiate argument, but I really don't recall mentioning not to check, I merely said that I would avoid FL sizing each and every time. Of course, you will notice that I said "if the brass was to be used in the same rifle", how could it become longer than the chamber of said rifle within one firing?!? The term "Fire-Formed" was not coined by me!!

Making a note of one particular rifle's fire-formed brass will allow a starting point to refer to. If you keep cutting (FL) brass to it's manufacture tolerance, you WILL destroy the brass.

(As no one else should, I do not take advice from forums or anywhere else without a thorough check of that information first, instead I go by ballistics professionals who write books on the subject)
 
Also, making a chamber cast will allow you to determine the exact size of a particular rifle's chamber. This will allow you to only FL size when absolutely necessary, extending the brass life and leading to higher accuracy.
 
One final word I will say, is that if you intend to use the brass in the same rifle everytime, I would avoid full length trimming too often. The brass will 'fire form' to the rifle chamber in question, and will usually only require neck sizing after the initial full length check/trim of the new brass. Full length trimming everytime will result in massive brass flow
. A fired case, no matter what chamber it was fired in, should always be checked for size (over all length) on every firing, & if it has not flowed forward, then it cannot be cut anyway...... never the less, the check should always be carried out,. it's too late when you cannot chamber your cartridge when need arises.
 
If you set up an FL die properly to only bump the shoulder back 0.001"-0.002" max there is no reason not to FL size unless you are a benchrest shooter using a single case for an entire match.
 
when i got some new nostler brass for my 22/250 i didnt full length size it. i loaded it up and shot it. then just neck size after that. of course i check the length of the brass after each firing.

well i understand its good to have your brass the same. most of the top brand names of brass shouldnt really need full length sizing when had new. i guess it depends if you feel the need to
 
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Always FL resize and trim new brass if for no other reason than that of uniformity. You will be starting with what you can assume are cases that are as close to identical to each other as you can possibly have at that moment. Trimming is a must, always.~Muir
 
If you set up an FL die properly to only bump the shoulder back 0.001"-0.002" max there is no reason not to FL size unless you are a benchrest shooter using a single case for an entire match.

This is how I normally reload used brass. I asked the question because after a few years I bought some new brass for the first time rather than buy new ammo and use the cases.

thanks again to all who replied. :)
 
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. A fired case, no matter what chamber it was fired in, should always be checked for size (over all length) on every firing, & if it has not flowed forward, then it cannot be cut anyway...... never the less, the check should always be carried out,. it's too late when you cannot chamber your cartridge when need arises.

No rudeness intended, but you guys need to read threads with a little more accuracy and attention. It was only one post before your's, but I'll make it easy and copy/paste the same post I wrote:

"I do not wish to initiate argument, but I really don't recall mentioning not to check, I merely said that I would avoid FL sizing each and every time. Of course, you will notice that I said "if the brass was to be used in the same rifle", how could it become longer than the chamber of said rifle within one firing?!? The term "Fire-Formed" was not coined by me!!"

Making a note of one particular rifle's fire-formed brass will allow a starting point to refer to. If you keep cutting (FL) brass to it's manufacture tolerance, you WILL destroy the brass.

Also, making a chamber cast will allow you to determine the exact size of a particular rifle's chamber. This will allow you to only FL size when absolutely necessary, extending the brass life and leading to higher accuracy.
 
when i got some new nostler brass for my 22/250 i didnt full length size it. i loaded it up and shot it. then just neck size after that. of course i check the length of the brass after each firing.

well i understand its good to have your brass the same. most of the top brand names of brass shouldnt really need full length sizing when had new. i guess it depends if you feel the need to

This is about the closest to what the "Ballistics Professionals" write in loading books. They write books for a reason, because they actually KNOW. (that is why none of us have written any books, we are NOT ballistics professionals!)

Personally, when it comes to fine details, I would prefer to stick with these qualified professionals. The books are written by companies who MAKE loading presses, and gun powder! Need I say more?!
 
The second post in this thread, by me. Using New Brass

Post number 4 on this thread, also written by me. Using New Brass

Some users seem to miss out half a thread when replying/disagreeing/commenting. We really need to actually read an entire thread, BEFORE we jump down each others throats with disagreements.
 
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