New vs once fired Lapua Brass Accuracy.

Shinigami

Well-Known Member
Has Anyone Noticed a difference in Accuracy between once fired and new Lapua brass, i personally just bought 200 new lapua 30-06 cases, and i have 40 once fired that i was going to use for load development but i was informed that due to the annealing on Lapua cases, that i'm likely to see a difference between the once fired and new. Please note that i have a reading full length bushing die, that i intend on using.
 
if your reloading the new lap brass becomes once fired once you fired it, you then carry on using your twice and thrice fired brass until such times as it starts to need annealing again or binning.
i don't notice a difference in accuracy during the first few or more reloading's
it could be argued that the new brass is less consistent than once fired as it has'nt been stressed yet
just my thoughts
 
Would love someone to explain exactly why the brass affects 'accuracy' with cited evidence.
 
Once fired is generally more accurate as it has been fire formed to your exact chamber dimension, I doubt it significant enough to be noticed though.
 
I have found my accuracy is better with 1/2/3 fired lapua brass than with virgin lapua brass
I think this is down to , the case being exactly fire formed to my chamber and once they have been fired I then resize with a neck bushing FL die and then I have great neck tension consistency, in experiments I have done with load development tests neck tension is just as important as seating depth and will change you size of group substantially ,lapua brass neck wall thickness I find to be very consistent unlike other brass manufacturers
this is with a 6mmbr and I was after the best accuracy and very low ES for long range shooting (1000 yards)
 
As with all accuracy topics, the reason for fire formed being more accurate (?) is meant to be that it offers greater consistency between shots...that is right up to the point that it needs FL sizing again and your pressures then changes...albeit probably not by much. Try out some strings of FL sized once fired on a chrony and then do the same for an exact same load on neck sized brass and compare ES and SD. Personally, I have never noticed much difference between FL and neck sized Lap brass once fired.
 
Brass is a complicated thing. Even brand new brass from the same batch has variations as it's an extruded material.
New brass will usually be good @ 1st firing, but much better afterward for three perhaps four firings. Then it should be anneald to retain optimum seal (obturation) & spring back. (Not a complicated process)
The seal is important to maintain consistent pressures round by round.

Retaining the fireformed concentricity and headspace by neck sizing is a short term solution to maintaining accuracy.
In my view, it's better to full length resize to your fired case headspace dimension. Doing this will produce extended case life.
It's not hard to set your f/l die to do this. You'll find how to set headspace on f/l dies all over the internet. It's also important to set your f/l die properly so that the decap rod doesn't offset the case neck from case body....thereby upsetting concentricity.

Once the set up is done, by sticking to a routine of annealing each 3-4 firings, full length resizing without bumping the case shoulders back more than .002", with the right load recipe for your rifle, your accuracy should be pretty damn good....all other aspects of gun care permitting.

However, this is only a first aspect of what's required with brass prep. The care you take and attention to detail is also a great help and will aid consistency. Consistency is what produces time after time accuracy.

A final point after seating the bullet is to maybe use a Lee Factory Crimp die, a consideration to 'even out' neck tension.
 
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A long time ago after a few reloads the accuracy of my .222R dropped off markedly, so I went to my gunsmith mate who helped me to trim them all to an even length and neck turn for consistency. The accuracy returned and so I went out and bought a full case trimming and turning station. I've used it ever since.
This usually happens after multiple reloads because brass flows. That's why we use it to make cases. But I suppose it might happen sooner if the case is loaded to the eyeballs or overbore already.
 
A lot will depend on the diameter of the neck portion of your chamber. If this is towards or at the top end of the allowed limits for your chamber then the brass will be worked more on resizing. Hot loads will make this worse of course as it stresses the brass more. The real life quality of the chamber reaming also makes a difference and some rifles leave the factories that maybe should not same can be said for barrels. Years ago was shown a .22 barrel from a quality European maker that the bore was way off center. This was discovered when the barrel was shortened at the owners request for the use of a moderator. It was not possible to cut the thread anywhere near concentric as the bore was that far out.
 
Some good and detailed replies. From experience I have found new brass even when resized is not as consistant as once fired. I now will not consider undertaking any load development with new brass.
 
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