New Brass V's Once Fired

Get or give advice on equipment, reloading and other technical issues.

Moderator: Mod

Message
Author
littlebang556
Posts: 344
Joined: Wed Oct 19, 2005 11:04 am

New Brass V's Once Fired

#1 Postby littlebang556 » Fri Sep 08, 2006 11:26 am

Is new F/L resized brass just as accurate as F/L resized once fired (in same rifle) brass?
______________________________
Fullbore = 5.56mm = 100.20 = smile
A.K.A........THE DREMELATOR
PUT Busselton RIFLE RANGE ON YOUR SHOOTING CALENDAR...THE GOLDEN BULLET...3rd Weekend In May. http://www.busseltonrc.com

AlanF
Posts: 7495
Joined: Wed Jun 15, 2005 8:22 pm
Location: Maffra, Vic

#2 Postby AlanF » Fri Sep 08, 2006 1:03 pm

Littlebang,

FL resized new brass will generally not be as good as FL resized fired brass.

But I wouldn't consider FL resizing new brass - you'll probably find it won't change it because its made ready to go easily into any standard chamber. For new brass I would seat the bullets into the lands and use a light load. This will fire-form the brass to your chamber and keep the case-head hard against the bolt-face so the case won't stretch. Then FL resize after that but try not bump the shoulder any more than just enough to chamber the case. Again, that will prevent the case from stretching when fired. If you don't take care of headspace, you can get head separation of cases after a number of firings.

Alan

littlebang556
Posts: 344
Joined: Wed Oct 19, 2005 11:04 am

BRASS

#3 Postby littlebang556 » Sun Sep 17, 2006 9:37 am

Well, I tried some of new F/L resized brass on the weekend. It chambered well, shot well but getting it out was another story. The bolt handle lifted fine but sliding it rearwards to extract the case was another story.
Does anyone have any ideas why this might be as I need a solution before the WA Queens shoot.

Regards

Robert
______________________________
Fullbore = 5.56mm = 100.20 = smile
A.K.A........THE DREMELATOR
PUT Busselton RIFLE RANGE ON YOUR SHOOTING CALENDAR...THE GOLDEN BULLET...3rd Weekend In May. http://www.busseltonrc.com

Peter Marum
Posts: 50
Joined: Tue Jul 26, 2005 1:25 pm

#4 Postby Peter Marum » Sun Sep 17, 2006 9:56 am

Robert,
1. Did you use the same brand of brass.

2. Did you back the charge back a couple 10ths grn.

3.With new brass it is best to soft seat the progectile
this allows for the new brass to fire form correctly.

Regards

Peter

littlebang556
Posts: 344
Joined: Wed Oct 19, 2005 11:04 am

#5 Postby littlebang556 » Sun Sep 17, 2006 10:02 am

Robert,
1. Did you use the same brand of brass.

2. Did you back the charge back a couple 10ths grn.

3.With new brass it is best to soft seat the progectile
this allows for the new brass to fire form correctly.

Regards

Peter


Yes Peter, all winchester brass.

Why does one back off a couple of tenths?

What is soft seating of projectile involve?

Finally, are you suggesting that I will need to fire form all my brass, is there no other way that will save my ever dwindling pile of reloading components?

Regards

Rob
______________________________
Fullbore = 5.56mm = 100.20 = smile
A.K.A........THE DREMELATOR
PUT Busselton RIFLE RANGE ON YOUR SHOOTING CALENDAR...THE GOLDEN BULLET...3rd Weekend In May. http://www.busseltonrc.com

AlanF
Posts: 7495
Joined: Wed Jun 15, 2005 8:22 pm
Location: Maffra, Vic

#6 Postby AlanF » Sun Sep 17, 2006 11:08 am

Rob,

I agree with Peter. If you do your first firing (or 2) with mild loads, the brass will be less likely to later expand excessively at the base, which is probably what is causing your extraction difficulty. Starting mild seems to "train" the brass to a lesser level of expansion at the base. BTW with your problem brass, you may also find that the primers are easier to insert next time because the primer pockets have expanded.

The above may serve as a workaround, but part of the cause may be a slight mismatch between brass, chamber and FL die. Top BR shooters start with a particular brand of brass (usually Lapua), then have chamber and die made to suit it exactly. So this mismatch could always put a limit on what pressures (and velocities) you can run. If this proves to be the case, I would try Lapua brass - it is probably the cheapest thing to change, and there's a good chance it will work better in your chamber.

Regarding soft seating, you can only do this if you have a neck bushing type die, and use a larger bushing than normal. This reduces the neck tension on the seated projectile. What you do is seat the projectiles longer than required to touch the lands, then as you close the bolt, the projectile reaches the lands then pushes back into the neck the required amount. This means the projectile will consistently be just touching the lands. A word of caution when soft-seating though, be careful when extracting a loaded round - the projectile may jam in the lands, and you'll get powder all through the chamber and action :shock: ! For fire-forming, it may be better not to soft-seat, but to seat firmly at a depth where the projectile is slightly jammed into the lands. The simplest way of doing this is to start by seating too long (i.e. the round won't chamber), then reduce by say .005 at a time until it will chamber. At that point it will be still be jammed some way into the lands, and will be good for fire-forming.

Hope this helps.

Alan :)


Return to “Equipment & Technical”

Who is online

Users browsing this forum: No registered users and 34 guests