308 sizing questions

[callen3615]

Hey guys. I have a few questions regarding sizing and the setup of a full length sizing die. First off Id like to thank everyone for all the help. Next, I have recently bought some winchester brass. I wanted to start with some fresh brass for my new press. I think it needs to be full length sized. In the "reloading 101" thread the OP says to take a new piece of brass that wont, or is difficult to chamber and start resizing in increments until no tension is felt. The problem is that my 700p chamber must be huge and it already chambers this new winchester brass without effort. So should I just load it up? or should I neck size it? If there is no resistance felt upon chambering then resizing isnt necessary is it? And if so how would i go about setting up the dies when I have no feedback to go on?

Lastly, I have been researching case resizing. Formally I just neck sized. I currently have the neck sizer set up in my press. The way I understand it is that if I just neck resize I will have to bump the shoulder back with a different tool/die later. But if I full length resize the die forms the case back to SAAMI specs thus bumping the shoulder and the entire case back to the way it was from the factory. I would like to keep necksizing tho. Could I set up the full length sizer so that it just bumps the shoulder back? So I could bump the shoulder back and neck size?


Thanks for the help guys.

 

[callen3615]

Re: 308 sizing questions

Ok. Figured out my first issue. It helps to read ALL the reloading tutorials before you post and look like a dumbass.

 

[vman]

Re: 308 sizing questions

Yeh new brass will need to be fireformed first.

It is highly unlikely that you will get a rifle that has chamber specs that are too short as they use go and no go guages at the factory.

Set your FL sizing die up so that the necks get sized and the expander runs thru the necks on their way out.

This will only be a temporary setting as once the brass becomes fireformed you will then need to readjust die height in the press to achieve minimal sizing.

 

[YAOG]

Re: 308 sizing questions

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: cpt. obvious</div><div class="ubbcode-body">Hey guys. I have a few questions regarding sizing and the setup of a full length sizing die. First off Id like to thank everyone for all the help. Next, I have recently bought some winchester brass. I wanted to start with some fresh brass for my new press. I think it needs to be full length sized. In the "reloading 101" thread the OP says to take a new piece of brass that wont, or is difficult to chamber and start resizing in increments until no tension is felt. The problem is that my 700p chamber must be huge and it already chambers this new winchester brass without effort. So should I just load it up? or should I neck size it? If there is no resistance felt upon chambering then resizing isnt necessary is it? And if so how would i go about setting up the dies when I have no feedback to go on?

Lastly, I have been researching case resizing. Formally I just neck sized. I currently have the neck sizer set up in my press. The way I understand it is that if I just neck resize I will have to bump the shoulder back with a different tool/die later. But if I full length resize the die forms the case back to SAAMI specs thus bumping the shoulder and the entire case back to the way it was from the factory. I would like to keep necksizing tho. Could I set up the full length sizer so that it just bumps the shoulder back? So I could bump the shoulder back and neck size?


Thanks for the help guys. </div></div>


You could also try using a Redding Type S Match Full Length Bushing die. These are pretty neat, full length resizing with selectable neck sizing all in one shot which maximizes concentricity and neck tension consistency significantly. These may work slightly better than Redding's Competition dies which I also have and still use.

Hope this helps!

 

[Nessal]

Re: 308 sizing questions

I don't bother to FL size new brass even in my custom barrel. You probably don't need to since your chamber is big as you have said. I just straighten the necks out and load them to fire form.

 

[jagged77]

Re: 308 sizing questions

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Nessal</div><div class="ubbcode-body">I don't bother to FL size new brass even in my custom barrel. You probably don't need to since your chamber is big as you have said. I just straighten the necks out and load them to fire form. </div></div>

+1

New case just need to be run through the neck expander ball to uniform them (as the case mouth can be dented / out of round from the factory) then deburred. Fire them then size / trim etc as you see fit.

 

[holdoff]

Re: 308 sizing questions

Capt,

Another to try is Forster's Bushing Bump die. This setup does not size the body of the case. It bumps the shoulder and allows the use of bushings to control neck tension. The die also allows the ability to adjust how much of the neck gets sized as well. The kit comes with 3 bushings that for me have been perfect for Lapua, Winchester, and LC cases.

This is a very nice setup: allowing fireformed body dimensions with the benefit of neck sizing, and maintains chambering reliability by moving the shoulder on each resizing. Also, by not totally sizing the neck, maintains sort of a false shoulder to help allign the case in the chamber.

 

[turbo54]

Re: 308 sizing questions

According the Zediker book "Handloading for Competition", the hot setup is to use a mandrel on new brass, to get the ID of the neck circular.

He recommends doing all your case prep work on fresh brass... Sorting, neck turning, primer pocket uniforming, flash hole deburring, trimming....etc etc. Finally, he recommends a full length size prior to loading.

Then to fireform using a full charge with the bullet seated into the lands (note that a full charge when in the lands is LESS charge than a full charge for bullets that jump!!!).

All that being said, you can feel free to load new brass - and use the bullet to make the neck round (not a good way to make good ammo though). The only sizing I think is really necessary is a neck size to get the neck nice and round and ready for a smooth seating of the bullet.

 

[jagged77]

Re: 308 sizing questions

When I've measured new brass it has always been sized or produced from the factory to minimum specs - therefore unless I screw my FL sizer as far down as it would go and still cam over in order to try and FL size the new brass, I wouldn't be really touching the brass. That's why I don't do anything other than uniform the mouth and deburr.

Unless you are after ultimate BR accuracy from new brass you can get away with minimum prep and still achieve excellent results.

Once you have the fire formed brass you can then go ahead and set up your FL resizer to suit your chamber, i.e. only bumping the shoulders back a couple of thou (same with Redding body die etc).

Each to their own, its whatever gives you the confidence.

 

[holdoff]

Re: 308 sizing questions

I agree with Jagged,

The mandrel method for cleaning up new unfired case necks works very well, especially for Lapua brass. When brand new the necks are very tight and if not opened slightly/uniformed can lead to higher than neccesary force when seating bullets.

I shoot out of a stock Remington, so chamber dimensions are generous. Full length sizing prior to the first firing is a waste of time. The quicker I can get new brass fireformed, the sooner I can get "serious" about reloading.

 

[turbo54]

Re: 308 sizing questions

Let me go ahead and throw this out there too:

From my experience with LEE and RCBS "expander ball" type neck sizers, along with [again, the Zediker book], the neck is sized way too small on the upstroke of the ram, and then the expander ball is forced to make it big again on the downstroke of the ram.

Say your fired case neck OD is .360", and for .002" of neck tension, your case neck OD needs to be .346...

Ideally, you'd want your sizer to size the neck down to .344, then the expander pull it back out to .346.

In reality, most neck sizers in this case would size it down to .330, and then back out to .346. This is simply extra work on your brass, and taking away case life.

A better methodology is to either modify your neck die by opening up the part of the die that sizes the neck down... Or to use a bushing die, followed by a mandrel.

 

[holdoff]

Re: 308 sizing questions

Turbo,

Avoiding additional work hardening of the case should be the goal of any sizing operation, thats why I forgo FL sizing new brass.

Many ways to skin a cat. Hornady and others will make a custom sizing die to your spec by using 2-3 fired cases from the chamber of your rifle. Or you can spec it however you would like.

This is essentially where we end up after finding the corrrect neck bushing size, combined with our particular preference for bump/body sizing.

Also, neck tension can be adjusted (increased) by altering the OD of the expander ball.