New Brass - Headspace and initial loading.

Griff24

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I'm about to develop a load for my Savage BA in 6.5 Creedmoor. After initial development I'll be loading 300-400 rounds with completely new brass for a prairie dog hunt. I'm new to reloading and have a good grasp on everything but headspace has me a tiny bit worried.

My question is what to do with the brass before loading? Full length re-size? Won't this push the shoulders down and increase headspace when it is already short because of the brass being never fired? Is there a way to adjust the die where it doesn't push the shoulders down?
 

Big Z

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I just run new stuff through a FL sizer...you could mark the neck/shoulder with a sharpie or smoke and work the die in toward the shellholder til you see contact, if you even get any on your new stuff.
 

thrusty

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I always full length my new brass too. Just to ensure consistency.

Put the shell holder in, raise the ram of your loader and screw the sizer in until it makes contact with the shellholder. This should put your sized brass within SAMMI spec. and will work for your rifle and others.

To find the actual headspace for your specific gun, you will need to measure your chamber....try Sinclair's chamber length gage. Sinclair Chamber Length Gage | Sinclair Intl

After you have this measurement, you can set your size die to bump the shoulder back only about 0.001" - 0.002".

I like using brass that was fired from someone else's gun that won't chamber easily in my gun. I then keep adjusting the sizer little at a time until the brass fits perfectly in my chamber and the bolt closes easily.
 
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FLIGHT762

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New brass will come head spaced below your chamber's minimum. I will usually run new , unfired brass through a neck sizer to iron out dents in the neck caused during shipping. That's all you have to do, unless you want to chamfer in & out, uniform the primer pockets, ream the flash holes or neck turn. That's up to you.

After the brass is fired in your rifle, be sure to bump the shoulders minimally (.001"-.002") so you don't over work the brass during F/L sizing. Weekly, there's one or two threads here in the reloading forum regarding reloaders that have no concept of what is or how to properly set up their F/L sizing die to resize and bump the shoulders minimally. If you don't know, do a search for shoulder bump. Lots of great information on this site.
 

Quack303Head

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^^^^ I do the same with new cases. Just let the die kiss the shell holder. This will make sure the case and mouth's are round.
 

Griff24

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Great info. It the die bottomed out won't size it out of spec then I'm good. Not optimal but not gonna blow myself up either.
 

FLIGHT762

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To find the headspace for your specific gun, you will need a measure your chamber....try Sinclair's chamber length gage. Sinclair Chamber Length Gage | Sinclair Intl

This chamber length gauge has NOTHING to do with the head space in your chamber. This gauge measures the length of your chamber in relation to how long the neck can be in your rifle before you have to trim the length of the neck.

If you want to measure the amount of shoulder bump you will need a head space shoulder bump gauge. A Mo gauge, RCBS precision mic, Hornady head space bump gauge, Sinclair bump gauge, Innovative Technologies headspace tool or the new Forster headspace bump tool all will give you the bump length in .001".

Here's a thread from a day or two ago regarding not setting up your F/L sizer properly and the results of that.

***http://www.snipershide.com/shooting.../182730-what-did-i-do-wrong-case-failure.html ***
 
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thrusty

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This chamber length gauge has NOTHING to do with the head space in your chamber. This gauge measures the length of your chamber in relation to how long the neck can be in your rifle before you have to trim the length of the neck.

I Stand corrected. I've never used the chamber gauge, but a friend recommend it to me. Now that you say that, I recall that the topic we had was regarding trim-to-length, not headspace.
 

msiebert

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Great info. It the die bottomed out won't size it out of spec then I'm good. Not optimal but not gonna blow myself up either.

Well...that's the way it is supposed to work. But, I have seen dies that set the headspace back more than what you might want too. Ideally, if the die bottom is contacting the shell holder that is supposed to set the headspace of the case to minimum chamber length {says SAAMI. } E.g., 1.630" for a 308. They usually will go .001-.002" under that. If you are concerned with ammo head spaced to your gun as you want to be for best accuracy and case life you really need to follow the advice in the above post and get the stuff to measure it so you know. Here is a tip I got from an old timer once... I went to a gunshow and bought a metric shit ton {just this side of an entire assload} of match 30-06 brass. It was so cheap and I was so happy. I was running around in circles crankin off...until I got home and measured it. It was like .015-.020" under headspace. The old dude told me to load it and seat the bullet out to touch the lands. That way there would be no excess headspace between the bolt face and the case head. It worked fine, all the cases fireformed back out to where they belonged. I just didn't load them hot.
 

ZiaHunter

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    I do not FL size new brass since most new brass will be smaller than your chamber and will increase the amount of stretch in the initial firing. This is especially true with belted cases. I fully prep all new brass for my precision rifles which includes using an expander mandrel on the necks then neck sizing to the desired tension. Dies are set up using fire formed brass and adjusted to set the shoulder back .001 to .0015. I have the IT gauge to be the most accurate when setting up dies for bolt guns and the RCBS Precision Mic for gas guns.
     

    Griff24

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    Well...that's the way it is supposed to work. But, I have seen dies that set the headspace back more than what you might want too. Ideally, if the die bottom is contacting the shell holder that is supposed to set the headspace of the case to minimum chamber length {says SAAMI. } E.g., 1.630" for a 308. They usually will go .001-.002" under that. If you are concerned with ammo head spaced to your gun as you want to be for best accuracy and case life you really need to follow the advice in the above post and get the stuff to measure it so you know. Here is a tip I got from an old timer once... I went to a gunshow and bought a metric shit ton {just this side of an entire assload} of match 30-06 brass. It was so cheap and I was so happy. I was running around in circles crankin off...until I got home and measured it. It was like .015-.020" under headspace. The old dude told me to load it and seat the bullet out to touch the lands. That way there would be no excess headspace between the bolt face and the case head. It worked fine, all the cases fireformed back out to where they belonged. I just didn't load them hot.

    Supposedly the way the barrel is attached allows Savage to set the headspace to SAAMI minimum every time. I should be fine given the info in this thread. I just didn't want to end up shoving the shoulders down enough to blow up this god awful expensive gun/scope. Not to mention my face. I'll probably just smoke the neck and move the die out until it doesn't mark the shoulder to be safe.

    I'll probably laugh at this post in few months but I'm overly cautious about this stuff since I'm not experienced.
     

    msiebert

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    " I'm overly cautious about this stuff"

    As very well you should be!!! Headspace and it's serious consequences is nothing to dismiss. The fact that you are overly cautious will be the reason you are still around to tell others how it's done properly.
     

    Deadshot2

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    " I'm overly cautious about this stuff"

    As very well you should be!!! Headspace and it's serious consequences is nothing to dismiss. The fact that you are overly cautious will be the reason you are still around to tell others how it's done properly.

    New Factory Brass is no different than buying new factory ammo. Just missing the bullet, powder, and primer.

    As others have said it's all sized to a minimum length so it will chamber in ALL rifles of that caliber (that were chambered to SAAMI spec's). As it was stated by others, just make sure that the neck is round by running an expander mandrel through it or just the expander ball of a F/L sizing die.

    Brass always performs better in a rifle after it is "Fire Formed". For second and subsequent sizings just use a fired case to measure the how low to set your sizing die. Should only set the shoulder back about .002" as measured by a headspace measuring tool like the RCBS Precision Micrometer or Stoney Point/Hornady headspace tool.

    If you just screw down the sizing die according to instructions, and size the brass to minimum length every time, the only thing you'll accomplish is to risk premature case head separations due to the case repeatedly stretching back to your rifles headspace dimensions. It stretches about 1/2" above the case head forming a thin spot that will fracture in a very short number of relaoding cycles. Just "bumping" the shoulder back enough to insure easy chambering and bolt closure will extend the brass life immensely. Some experience brass life of 30-40 cycles although the average is more like 15-20. Sure beats having to replace brass after only 3-4 reloads.