New brass sizing differently than fired

[TDH]

Recently bought some new brass to start reloading for my 204. I set my die up using deprimed Hornady brass that was fired through my gun. Bumped the shoulder back .001" verifying with calipers and the Hornady headspace adapter. When I run the new Dogtown brass through the same setup, it is .006" shorter. Is this a normal thing with new brass since the neck is softer? I didn't see any other threads discussing it and have always reloaded using fired brass. Wasn't sure if I should just adjust the die or if I was missing something.

Hornady new unfired ammo measures 1.551"
Hornady brass fired through my gun 1.552"
Hornady fired brass ran through the sizing die 1.551"
New Dogtown brass 1.553"
New Dogtown brass ran through the same sizing die 1.545"

Sizing die is a Forester full length sizer. To get the .001" bump on the fired brass, the die is set just shy of an 1/8 of a turn after it contacts the shell plate.

 

[BenPerfected]

I am not a expert on sizing brass, but I also use a full length Forester sizing die. My shoulders are bumped .002-.003 at Foresters recommendation.
Ben

 

[dstoenner]

Yes different manufacturers of brass have different results. I use a set of Redding competition shell holders and keep a 3x5 card on which one is required to use for each brass manufacturer. When I don’t know I strait at -0.010 and work up measuring each step till it is set back correctly

Worth their weight in gold.

I also always set my sizer up so as the bottom of the sizer just kisses the shell holder as the ram cams over. That way you always have a constant volume which eliminates any dimension differences for different hardness of brass.

David

 

[Billy 30-06]

I have noticed with new once fired brass I can set up the FL sizing die to bump the shoulder back .002" and after quite a few firings that number gets less. It may be the brass is springing back some due to hardening. .006" seems extreme. Your press may be springing some during sizing.
Billy

 

[BenPerfected]

I have noticed with new once fired brass I can set up the FL sizing die to bump the shoulder back .002" and after quite a few firings that number gets less. It may be the brass is springing back some due to hardening. .006" seems extreme. Your press may be springing some during sizing.
Billy

Might be time to anneal your brass. How often?.........that’s another thread.
Ben

 

[JFrank]

I’m no expert either but I’m curious about one thing.
Your saying that Hornday fully fire formed brass is only.001 longer than new un Fired Hornday brass ?

 

[Billy 30-06]

Might be time to anneal your brass. How often?.........that’s another thread.
Ben

I haven't annealed my brass. I just checked some Federal brass that have been loaded more than 10 times that were 2.676" fired and 2.675" sized. My Lapua brass that haven't been loaded near as much measured 2.674" sized.
Billy

 

[Ned Ludd]

Typical virgin match brass is usually shorter than fire-formed brass in the base to shoulder dimension by any where from .004" to as much as .008". If you have set your sizing die properly to bump the shoulders of fire-formed brass back only ~.001" to .002", it should not be bumping the shoulders of virgin brass back at all (the working assumption is that we're talking about the same brand/Lot of brass here). I use my FL sizing sizing dies (set for ~.001 shoulder bump with fired brass) with virgin brass regularly to improve the neck tension as compared to straight out of the box. The shoulders don't move.

In the case you described above, it's a different brand/Lot of brass with different measurements. Your best bet is to purchase a separate sizing die for the different brass. The alternatives are: 1) accept the fact that you'll be bumping the shoulders of the Hornady brass far more than necessary if you use the same sizing die for both types of brass; OR 2) adjust the die appropriately every time you switch between brands/Lots of brass, which would be a huge PITA, IMO.

 

[TDH]

Thanks for the comments. I backed off the sizing die and will get a few loaded to see how they fire form. Then adjust the sizer based on that.

 

[Zero333]

different brass works differently.

 

[Billy 30-06]

While we're doing all this measuring I just measured some new unfired Lapua .308 brass I ran through my Sizing die to uniform the necks that came out at 2.671". That's = .005" less than fired in my chamber.
I would go and shoot your new Dog Town brass and not worry too much about the .006" head space.
Billy

 

[Zero333]

O.OO6" should still pass a field gauge, so you're good to go.

 

[JFrank]

I’m no expert either but I’m curious about one thing.
Your saying that Hornday fully fire formed brass is only.001 longer than new un Fired Hornday brass ?

Still curious

 

[up80ct]

Recently bought some new brass to start reloading for my 204. I set my die up using deprimed Hornady brass that was fired through my gun. Bumped the shoulder back .001" verifying with calipers and the Hornady headspace adapter. When I run the new Dogtown brass through the same setup, it is .006" shorter. Is this a normal thing with new brass since the neck is softer? I didn't see any other threads discussing it and have always reloaded using fired brass. Wasn't sure if I should just adjust the die or if I was missing something.

Hornady new unfired ammo measures 1.551"
Hornady brass fired through my gun 1.552"
Hornady fired brass ran through the sizing die 1.551"
New Dogtown brass 1.553"
New Dogtown brass ran through the same sizing die 1.545"

Sizing die is a Forester full length sizer. To get the .001" bump on the fired brass, the die is set just shy of an 1/8 of a turn after it contacts the shell plate.

what do you think about that dog town brass and would you buy more of it.

 

[jepp2]

Hornady new unfired ammo measures 1.551"
Hornady brass fired through my gun 1.552"
Hornady fired brass ran through the sizing die 1.551"
New Dogtown brass 1.553"
New Dogtown brass ran through the same sizing die 1.545"

A number you don't list is what length gives bolt contact when you close the bolt on the sized brass. That is a number I record for everything I load for (some folks call this the zero headspace). Then I set my die to be -0.002" from that length.

And when I am setting up the die, I will typically back it off and remove the expander. This way I can start lowering the die until I reach the proper case head to datum length. By doing this without the expander, I am not working the case neck as much. Then I put the expander in, and start sizing my cases, initially checking each one to make sure everything is working the way I want it. After that, my checks are much less frequent, but I still do them.

"Hornady brass fired through my gun 1.552" - a single firing on the brass rarely gives you the full chamber length. Unless your loads are really hot, it make take several firings. So the "zero headspace" on your rifle is probably much longer.

Did you happen to try chambering any of the new Dogtown brass before you decided it needed to be sized? Seems you based the need for it to be sized on the 1.552" Hornady fired brass measurement. The 0.006" shoulder movement is much more than I ever experience with the same die setting for different brass.

 

[dkhunt14]

Typical virgin match brass is usually shorter than fire-formed brass in the base to shoulder dimension by any where from .004" to as much as .008". If you have set your sizing die properly to bump the shoulders of fire-formed brass back only ~.001" to .002", it should not be bumping the shoulders of virgin brass back at all (the working assumption is that we're talking about the same brand/Lot of brass here). I use my FL sizing sizing dies (set for ~.001 shoulder bump with fired brass) with virgin brass regularly to improve the neck tension as compared to straight out of the box. The shoulders don't move.

In the case you described above, it's a different brand/Lot of brass with different measurements. Your best bet is to purchase a separate sizing die for the different brass. The alternatives are: 1) accept the fact that you'll be bumping the shoulders of the Hornady brass far more than necessary if you use the same sizing die for both types of brass; OR 2) adjust the die appropriately every time you switch between brands/Lots of brass, which would be a huge PITA, IMO.

Not with die shims. Changing bump is easy peasy. Matt

 

[thatguyshm]

what do you think about that dog town brass and would you buy more of it.

I picked up 243 Dogtown brass for a new rifle. It's tough brass but it takes some work to get it ready. I've found that the primer pockets are tight and the necks are a bit out of concentricity. I use a Lee collet neck die and pass each piece of brass through twice at 90° opposing planes to try and bring them back in. After a firing it seems to be nice and straight and you can square up the pockets if you please.

I struggled to get SB primers into the brass but CCI 200s went in nicely. Weight is good the spread in 15 random selection was within 2.5gr. It's not match brass but you aren't paying match prices either. All primer holes need to be deburred.

I also found that they are not undersized, which I like. My chamber is a tight chamber, meaning minimum headspace. I used a body die to set a proper 0.002" shoulder bump, some new cases unsized were a tight fit when chambering.

I like doing the work to the brass, it's a great winter project and it's all ready to go. I've found the brass to be strong and would recommend to anyone willing to process it properly .