Neck size new brass

[Jimlaw83]

Much as been said about fireforming brass before neck sizing and really fine tuning loads. However, since my Forster FL die sets my 260 neck tension at .005+, what is the harm of going ahead and FL sizing the new lapua brass, then running it through my Lee Collet die with .002 tension? I checked and shoulders aren't buckling or anything, but it just seems to me that too tight neck tension is an unnecessary part of fireforming/initial load development.

I have my charge down to a .3-.4 grain window that I will tune after first firing, but I was thinking of going ahead and dispensing with neck tension issue as well as determining optimal seating depth on the brass's first firing. Any problems with this?

 

[BoilerUP]

Re: Neck size new brass

My experience with Lapua 260 brass is that it does need to be sized prior to first loading.

In my 260 barrel (0.298" no turn neck), virgin Lapua brass that was simply loaded showed excessive pressure signs due to high neck tension. When I ran some through a Lee Collet die, I encountered great resistance from the decapper/sizing pin and still saw pressure signs.

I found FL sizing the brass prior to first loading (same loads as virgin unsized and virgin neck sized) completely eliminated pressure signs and provided even neck tension.

 

[varmint slayer]

Re: Neck size new brass

Sizing of any kind on new Lapua brass (short of a dented case or something) is like wiping your ass before you shit IMO. Just load and go. Just my two cents.

 

[MtnCreek]

Re: Neck size new brass

IME, all new brass needs to be sized. It's common, even with high quality brass, to have out of round necks.

Have you considered getting an oversized expander ball for your full length die and turning it down to your specs?

 

[Jimlaw83]

Re: Neck size new brass

I did pick up an extra lee collet mandrel for my intended long term neck tension. I don't have any issues with full length sizing before first firing, but I guess the question was more along the lines of whether it is ok to follow up that FL size with a neck size to get my desired neck tension...all before first firing. I haven't tested, but I would guess pressures, velocities, even accuracy nodes may be different due to the neck tension differences, so why not go ahead and eliminate that variable?

The general consensus I've found is that rough charge weight and seating depth are ok for first firing, then fine tune variables (powder, depth, primer, neck tension) are best left for after 1st firing, and the tension part doesn't seem like it has to wait. However, experience trumps theory, which is what led to the post.

 

[MtnCreek]

Re: Neck size new brass

The collet die won't hurt anything; the way it works, you're not really adding any work to the brass either. Unless your chamber is really tight, I doubt you'll need to FL size; just use the neck die.

I've had mixed results w/ the Lee collet die, probably my fault. If it were my brass, I would tune the fl die to give the neck tension I was looking for and stick w/ it.

Good luck with the new loads.

 

[ksthomas]

Re: Neck size new brass

Jimlaw83,

Officially, we adivse that all new brass be run over a mandrel or neck size die prior to its first loading, simply to assure that the brass is perfectly round and to even out neck tension, as others have mentioned here. Full lenght sizing wont hurt anything, but it really isn't needed, either. In most instances, it will probably make very little contact with the dies body.

Incidentally, on a personal note, I'd recommend this neck processing step with <span style="text-decoration: underline">any</span> new brass, regardless of make. It's just the handloaders form of "due diligence" in making sure that everything is "right" before we chamber the first round.

 

[Deadshot2]

Re: Neck size new brass

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Kevin Thomas</div><div class="ubbcode-body">

Incidentally, on a personal note, I'd recommend this neck processing step with <span style="text-decoration: underline">any</span> new brass, regardless of make. It's just the handloaders form of "due diligence" in making sure that everything is "right" before we chamber the first round. </div></div>

+1 on this advice. I use either my Lee collet die or Sinclair Expander die just to make sure there are no dings or undersized necks. It only takes one to make one a believer and yes, it CAN happen to lapua. Not as often as with other brands but stil can.

 

[Jimlaw83]

Re: Neck size new brass

Neck size it shall. I will double check brass chambers ok just to be safe. Thanks much!

 

[leadbullet]

Re: Neck size new brass

load it out of the box or go haead and size it if it makes you feel better. Either way won't hurt anything.

 

[majohnson2]

Re: Neck size new brass

I wouldn't see brass mfg resizing the cases after the original stamping. Sorting bullets, or spending as much time as we do, working cases like we do in order to achieve as much accuracy and performance.

Shooting cases through the intended gun prior to loading for any kind of match is a must. Reloading is all about consistency from brass, bullets, and powder.

 

[Scooter64]

Re: Neck size new brass

fwiw i loaded ten round test load with new winchester brass and found that when i seated the heads i did not get consistant seating depth when i checked each round with my rcbs precision mic. i pulled the head and ran them through redding neck dies that fixed the problem.