Can someone explain .308 headspace to me please?!
- Thread starter Sheprador1973
- Start date
As I posted above, you will not be able to set the shoulder back a couple of thou with a Lee FL die. It’s all or nothing.Really glad you posted this, for my sake but also that of others with less experience. It is easy to assume, even when having digested the literature that accompanies a die set, that FL sizing ONLY sets your case back to factory spec. Little to nothing is mentioned about different degrees of FL sizing and/or using your own chamber as the primary reference point.
I'll get the rifle out tomorrow and follow the thorough advice given above. In relation to the aforementioned shelved brass, if it is oversized (bit of a confusing term as implies 'bigger') as suspected, the bolt will drop under gravity alone?
Thanks very much...will report back.
Your experience is different to mine . I've had Lee dies that would bump size perfectly , in saying that there's been several threads where they've been unable to get them to size at all , which would imply poor quality control on Lee's part .
Sheprador1973
Well-Known Member
Had sleep and coffee so better placed to get it this morning.
I misinterpreted the above i think...you're not FL sizing every 3rd firing to bump the shoulder back for example .003", the Lee dies can't do that. You use it to bump the shoulder back as far as the die is capable (as you say its effectively all or nothing)?
Forgive my relative ignorance, but there appears to be a huge amount of misinformation, or at least vastly different interpretations out there. Even this short thread has some saying Lee dies are perfect for bumping the shoulder back, while others claim they cannot do it at all (at least a few thou or so).
Sheprador1973
Well-Known Member
Would you be able to explain this a little please ER? I've heard the expression many a time but unsure of the details and whether it applies to all press types (mines a Lee cast press...challenger? Not sure). Could Google it but would rather ask the experts here as there's some wildly conflicting reloading advice out there. Thank you
Sheprador1973
Well-Known Member
Considering all the above, could someone please recommend a FL die that is capable of incremental bump sizing in .308?
Sheprador1973
Well-Known Member
An important distinction...thank you
maximus otter
Well-Known Member
Headspace is simply the distance between the bolt face and whichever part of the round prevents the cartridge from moving farther forward.
In .22LR it's the rim; in some self-loading pistol rounds it's the neck of the case; in belted rifle cases it's the belt, etc.
maximus otter
People make things far too complicated - the less they know, the more complex jargon they make up too. A Lee FL die is all that is needed. It just needs to be adjusted properly in the press.
@Sheprador1973 , there should be plenty of instructions online on how to set up a FL die to size correctly for your rifle chamber. This is one of the first things you should have been taught when you started reloading.
A good rule is to not to resize a whole batch of brass without first checking fit in the rifle.
@Sheprador1973 , there should be plenty of instructions online on how to set up a FL die to size correctly for your rifle chamber. This is one of the first things you should have been taught when you started reloading.
A good rule is to not to resize a whole batch of brass without first checking fit in the rifle.
Just going on my experience in Lee dies which I use in .223, .308, 6.5x55 and 6.5 creedmoor. If the die isn’t set as the instructions and the press cams over the shoulder doesn’t move.
Other dies such as RCBS, Redding, hornady etc do allow a small bump.
FWIW yes I am fully resizing which bumps the shoulder a fair bit probably equal or more than your 6 thou and I’ve never had an issue with light strikes.
I’ve use Lee does in several calibres and I’ve never managed a small bump, when set up exactly as the instructions! No complex jargon it just doesn’t work in the calibres mentioned above and in a Lee press if that makes any difference!
The Lee instructions make no reference to sizing to the shoulder back to the chamber, just resetting to factory dimensions. There is no adjustment mentioned for varying shoulder bump/ headspace so I don’t think I’m making is up!
From the Lee website.
Essentially if the die is not adjusted down far enough the shell holder does not touch the base when sizing and no sizing takes place (as explained below) so you have to wind it down until they touch, which fully resizes.
This explanation from Lee is exactly what I am saying, all or nothing, so I am not making up jargon or displaying ignorance of Lee dies.
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kenbro
Well-Known Member
I sometimes only size part of the neck but I cycle the cases through the action before loading them.
And when loading them I put powder in some…..
.Ken.
phaedra
Well-Known Member
Dies do not "cam over" certain presses do (RCBS Rockchucker) and some don't they just dead stop (Lee Breech Lock etc).
Caming over just means the die is in full contact with the shell holder and the presses mechanism is designed to do it, the die cannot travel any further as it's already in full contact with the shell holder.
Once the die is in full contact with the shell holder the amount of neck bumping back is at it's maximum, you can increase it, usually by using a modified shell holder (Hornady etc. sell them) this raises the case height within the shell holder by a measured amount so at full contact with the shell holder the case is higher into the die that with a normal shell holder thus bumping the shoulder further back.
Reducing shoulder bump can be done by unscrewing the die by a small increment, this means the case won't be pushed as far into the die and the shoulder won't be bumped as far back as it normally would.
Caming over just means the die is in full contact with the shell holder and the presses mechanism is designed to do it, the die cannot travel any further as it's already in full contact with the shell holder.
Once the die is in full contact with the shell holder the amount of neck bumping back is at it's maximum, you can increase it, usually by using a modified shell holder (Hornady etc. sell them) this raises the case height within the shell holder by a measured amount so at full contact with the shell holder the case is higher into the die that with a normal shell holder thus bumping the shoulder further back.
Reducing shoulder bump can be done by unscrewing the die by a small increment, this means the case won't be pushed as far into the die and the shoulder won't be bumped as far back as it normally would.
Bavarianbrit
Well-Known Member
Or by adding some feeler guage leafs say 3 thou worth under the case head so pushing the shoulder higher into the die.
MAH
Well-Known Member
Hi. Are you aware of these?
You FL die might not be the problem.
You may inadvertently be using a none standard case holder.
This product is designed to increase or reduce Headspace.
M
Redding #1 Competition Shellholder Set (11601)
What press out of interest? I wonder if that makes a difference.
Even the Lee instructions above say that the dies do not size the case until the shoulder is right at the top of the die so the shell holder should contact the die. That could only ever give one, absolute, case dimension.
This is true of 5 or 6 Lee FL dies I’ve used over the years so not just a one off.
Sheprador1973
Well-Known Member
Yes, for clarity they're the Lee case holders.
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