Adjusting body diameter and shoulder bump separately for .308 cases

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What I discovered today is that I have to set the Redding small base .308 sizing die all the way down to "cam over" depth in order to get the the case head barely small enough to chamber. This results in the shoulder being bumped back more than necessary.

There are a few variables in play but if you have a case that is sized “small” or “under” that would mean it’s towards the minimum specifications. If you are also shoving the shoulder back “too far”, you realize that you should stop doing that.

Going from just the OP.

What I discovered today is that I have to set the Redding small base .308 sizing die all the way down to "cam over" depth in order to get the the case head barely small enough to chamber. This results in the shoulder being bumped back more than necessary.

Any ideas on how I can solve this?

I would stay away from brass not shot from that rifle, to narrow your focus, for that rifle or get some head space gauges and see if it needs to be fixed.
 
Reloaders can not size 308W cases fired in a machine gun; There is something about the case's ability to resist sizing the reloaders does not understand.

I disagree with that statement. It can be done easily if you anneal prior to trying to size. Now if you don't anneal the odds are they will not size back far enough as you said. But even if you do size them the brass is 0.020"+ more longer than any fired in a bolt gun. So you will/may have case head separation on the first firing. The main reason it's not suggested to use MG brass, not worth the effort.
 
But even if you do size them the brass is 0.020"+ more longer than any fired in a bolt gun. So you will/may have case head separation on the first firing. The main reason it's not suggested to use MG brass, not worth the effort.

If the case length from the shoulder/datum to the case head is .020" longer than the same case fired in a bolt gun why didn't the case suffer case head separation the first time it was fired?

Annealing; there has to be something about annealing I do not understand, if I anneal a case I anneal the neck and shoulder, if I have a case head separation it will happen between the case head and case body. Not for here; I anneal, but I will guaranteed my annealing is nothing like anything a reloader on an internet forum has ever seen.

F. Guffey
 
First of all, the headspacing on most 7.62 NATO chambers will run 0.006 to 0.010 inch longer than their sporting rifle counterparts, to allow for proper feeding and ejection during repeated, rapid firing. Combine a longer chamber with a thinner case—the .308 Winchester cases will be thinner than military 7.62 NATO cases—and you open the door for the possibility of a ruptured case. A good rule of thumb is that a .308 Win. chamber can handle both types of ammunition, but a 7.62 NATO chamber should only fire 7.62 NATO ammunition. This avoids any potential problems in a chamber with intentionally excessive headspacing.
https://www.shootingillustrated.com/articles/2018/8/19/308-win-vs-762-nato-whats-the-difference/

Many FAL are made from parts kit.
 
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Ain't that the truth.

Mine was built by a Gun Designer friend whose shop is full of milling machines and metal lathes.

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He started with a new IMBEL receiver, he said, just as good as an FN, and parts kits. He asked me if I wanted "all correct" or best fit. I wanted best fit, and he tried to give me as good of a trigger as possible as he knows I am picky about this.I had him install a long South African buttstock as I am a stock crawler.

He drilled and tapped the rear sight so I could install sight inserts.

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The flash suppressor, pistol grip, cocking device, and operating rod are American, which met content laws at the time. But the rest, particularly the barrel and bolt, are military. I did not ask and I did not care if he set up the locking block to SAAMI or NATO. I think he set the chamber to SAAMI. Bud had been deployed, and as the most knowledgeable gun person in the unit, maybe theater, he was asked to go through and gauge the unit M14's. They had M14's to shoot land mines. The rifles were from inventory, might have been new since 1964, and all of them swallowed the SAAMI Field gauge. That surprised Bud. But what that told him was that military chamber headspace can be widely different from SAAMI commercial. Another good reason to lubricate your cases in a military chamber to avoid case head separations. These parts guns are what they are, and if the parts align to military standards, well, they were supposed to.

And, this is important, these FAL's were never target rifles and while their accuracy can be improved on with better barrels, tighter parts, pretty much they will never ever be target grade. These rifles are battle weapons not prissy precision weapons that jam with a tiny pinch of dust. Attempting to make it something else will only create problems. Instead of parroting Benchrest reloading practices, the ammunition for these rifles should be built with the primary expectation of chambering and ejecting. And that means a case smaller than the chamber.
 
I probably don't have a popular opinion on this, but aI think reloading for a FAL is a fools errand.

What with so much good, economical NATO on the market right now from GGG, PPU, and MEN among others, it just doesn't pay unless it is your form of therapy.

A FAL shoots the way it wants to, not the other way around; hitting 12" steel @ 200m with irons is all one could ask for.

Conelrad, having fondled & fed FALs for over 4 decades.
 
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Following Slamfire's sage advice I bought one of these gauges and it arrived in the mail late this afternoon.

I immediately unpacked it, ran to the reloading room, and popped a handful of fired, full length resized, and trimmed cases into it. With the very first piece of brass I discovered that the problem I was having wasn't with the shoulder bump or the diameter of the case body near the base. It was with the case neck. The reason for the many failures to chamber a resized case in the rifle was that the case neck diameter was too large or lopsided!

How do you spell relief - Sheridan slotted ammunition gauge. I was driving myself crazy trying to figure out the problem. Being able to actually see the front end of the case in the gauge was like a bright light being turned on in a dark room.

Next questions. My Redding full length sizing die doesn't touch the neck. Some of the once fired brass case mouths are dented. What's the preferred method for pushing the dents out? Do you folks do anything about the case neck diameter prior to seating a bullet in a semi-auto rifle?
 
My Redding full length sizing die doesn't touch the neck. Some of the once fired brass case mouths are dented. What's the preferred method for pushing the dents out? Do you folks do anything about the case neck diameter prior to seating a bullet in a semi-auto rifle?
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The expander should correct most of it. 20191120_191404.jpg When fl sizing.
 
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My Redding full length sizing die doesn't touch the neck
The FL die with expander ball should size the necks down more than needed and then the expander brings them back up to where neck tension will be good but not too tight. If it isn't doing that, Redding will replace it.

An easy check is to size a couple of cases without the expander ball/decapping stem in the die and see if the necks clear the gauge. If they do, you have an expander ball issue.

This is my best guess anyway.

Those Sheridan case gauges are great, and can save a lot of head scratching.
 
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My Redding full length sizing die doesn't touch the neck. Some of the once fired brass case mouths are dented. What's the preferred method for pushing the dents out? Do you folks do anything about the case neck diameter prior to seating a bullet in a semi-auto rifle?
Steve, apparently what you have is a "Body Die" rather than a "Full Length Sizing Die" (FLSD). From Brownell's description: "Body Dies are designed to full length resize the case body, bump the shoulder position for proper chambering, but not size the neck at all....."
Many people report great success using a "Lee Collet Neck Sizing Die" as a separate step after sizing the case with a body die.
Another option is to obtain an actual FLSD to size the entire case in one operation.
In any event, sizing the neck is a must with a semi-auto rifle.
 
Steve, apparently what you have is a "Body Die" rather than a "Full Length Sizing Die" (FLSD
That may be the answer, if he does my simply test he'll know. Or maybe the info on the die will tell him. I do not have a Redding body die so I don't know how they are marked.
Another option is to obtain an actual FLSD to size the entire case in one operation.
That's the best way to load for an auto feeding .308, IMHO.
 
Yes but if your bought the S bushing die it has the top parts for expanding/depriming and to hold the bushing inplace. I need to look at mine to see what markings are on it.

My body die is marked " B / FL "
 
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There had to be a 'before' as in 30/06 before the M1 Garand, I had to go back to 1954 to find information.

F. Guffey
 
Adjusting body diameter and shoulder bump separately for .308 cases

Good question; how does a reloader control the diameter of the case when sizing? And then there is that part about bumping? Separately? If the die is one piece how is it possible to control the diameter of the case and bump? the shoulder separately?

F. Guffey
 
My die is one piece, my die has threads, my die sizes the case body, my die headspace’s a case by way of threads, I can easily adjust the headspace using a simple feeler gauge. I do not understand how a single die could move separately.
Again I’m probably missing something
 
No, just our buddy being intentionally vague, "to make people think" is what he has said about his style. :)
 
Again I’m probably missing something



I do not understand how a single die could move separately.


Adjusting body diameter and shoulder bump separately for .308 cases


I have absolutely no interest in making another die that could be used to size the case body and shoulder separately (at the same time). Because I have tried to bump a shoulder back with a die that did not have case body support I claim it is impossible to move the shoulder back with a die that does not have case body support. I could say a seating die does not have case body support, I could say crimping only requires a hint of effort but when too much crimp is applied the neck and shoulder is moved back. Moving the shoulder back causes the shoulder/case body juncture to bulge; again it bulges because the seating die does not have case body support.


It has nothing to do with making anyone think, it should not be necessary to get a reloader to want to think. And then there is the reloader that is motivated to think.


Again, reloaders believe they can move the shoulder back and or bump it back because they believe that is the direction the shoulder moves when sizing. When I size a case the shoulder does not move back and I do not care how fancy I get with the ram and handle I find it impossible to bump the shoulder back; because bump is a function of the press if it is a cam over press. Again, I have three Rock Chucker presses; I do not have a Rock Chucker that cam over. I did modify one Rock Chucker many years ago to cam over.


The last RCBS press I used that was a cam over press was the A-2, it had .017" cam over meaning it was a big time bumper. I accused the owner of the press of modifying the press. His modifications increased the amount of bump. The .017" bump was equivalent to lowering the die 1/4 turn.


F. Guffey.


My cases do not have head space; SAAMI doe not use the symbol for head space in their drawings of case specifications, SAAMI doe use the symbol for head space on their drawings of chamber drawings. MEANING? If I was a thinking man I would think my chamber has head space and I would think my cases do not have head space. And then we had one member on many forums call SAAMI to inform them they made a mistake because he spent many years claiming the case had head space. I use the length of the case to off set the length of the chamber.
 
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