Belted Cases Are A Pain

[Truc]

Quote, What I do now is use Redding Competition Shellholders that allow you to bump the shoulder back .001 to .002 inches smaller than the chamber. This effectively eliminates headspacing off of the belt. If I were to run across any brass that is hard to chamber, I would just throw it away. But right now using Nosler brass I have not had a single issue through several different batches of brass for both 300 win mag and 338 win mag.

There is another way to accomplish this and that is to use shims under the die, the shims start at .003" and go up to .010". You set the die to size too much then install the shims between the die and the press. This is common in shooting Benchrest as new brass needs less sizing than older brass.

 

[MagnumManiac]

Every design, belted and not, has problems (duh).

As this thread demonstrates, it is a hot debate subject. I'm not fond of belted designs.

Many people here have more experience with belted case designs than I do.
but
It seems to me that if you have a chamber that is within spec there are no problems.

If your chamber is not in spec then the experienced guys have work arounds and extra tools to overcome the problems that just don't exist in non-belted cases.

The two things I have encountered are long chambers and wide chambers.

Long chambers wreak havoc on the brass by allowing it to stretch at the belt body junction. I have seem more case head separation on belted designs than any others.

Bulging just in front of the belt or including the belt itself. Since the resize dies do not compress the belt or the belt body junction, your stuck. If you lower the die to resize this area then you are over working the brass in this area and inducing case head separation. There is a collet tool that fixes this but it is another tool...

With a couple exceptions every belted design rifle I have was or will be rechambered or rebarreled.

So far I've worked with:

• 270 Wby two rifles, both rifles within spec. In fact, they had the same fireformed dimentions. One was rebarreled anyway.
• 300 Wby three rifles, 2 within spec. one with a fired case length that was .020 longer than the others, that one was used as a donor. A custom on a Hall repeater action will be rechambered to RUM. The 'factory' one is fine but allows the belt to grow a little. Not requiring a 'fix' though.
• 338 WM, No problems with this one but its getting rechambered to 338/26 Nosler

Depending on how the world goes I may be able to get some 257 Wby loads made and test fired to see how the chamber is on that one.

Have you ever sectioned a belted case to see it's construction?
To swell the belt, which is below the web and part of the solid head , would take a fair overload. I have used the CHE method on my 300WM cases, along with my pressure trace 2 equipment, even at 70,000psi, the rear section of the belt will expand .0001"-.0003", although at 80,000psi it may expand .0005"-.001", which in turn has an oversize pocket that will no longer hold a primer.
With normal maximum pressure loads the belt will NOT expand as you say.
The cause of head separations is not the fault of the belt, it is caused by the shoulder being pushed back too far in the FL sizing die, each time the case shoulder stretches forward to meet the chamber, the case is stretched from the web forward, it has nothing to do with a bulge or the belt, the headspace dimension of the belt on a cartridge DOES NOT CHANGE, it can't because it is a mechanical dimension on a solid piece of brass, if it is .218" when the chamber is cut, it stays at that dimension. The only thing we can do is forget the belt exists and headspace off the shoulder, which supports the cartridge more precisely and only requires .002" clearance to function and overcome the belts dimensions.
The reasons that cause head separation is IDENTICAL in all case designs, excess headspace is the ONLY cause, either by the chamber dimensions, or more importantly, the OPERATOR of the FL Sizing die. Most people have no idea on how to set up FL Sizing dies CORRECTLY. In most instances, whether belted or NOT, hard chambering is caused by a die set up just touching the shell holder, this leaves the head to shoulder dimension too long, not always mind you, it depends on your chamber dimensions, but it happens more times than not.
Just because you don't understand belted case headspace doesn't mean your theories are correct, the belt poses no problem, never seen a single problem firing unfired new brass, it's only whennit's sized incorrectly does a problem exist.

gun)

 

[Deleted member 46119]

...
Just because you don't understand belted case headspace doesn't mean your theories are correct, the belt poses no problem, never seen a single problem firing unfired new brass, it's only whennit's sized incorrectly does a problem exist.

gun)

I detect an attempt to start a flame war. How original.

 

[davkrat]

Quote, What I do now is use Redding Competition Shellholders that allow you to bump the shoulder back .001 to .002 inches smaller than the chamber.

Is there any bonus to using the longer shell holders vs just adjusting the depth of the FL die? I assume the shell holders make it easier and more reliable to make a .002" adjustment but I've always simply sized the case a little bit more until the cases will just chamber then lock down my die and forget about it. Belts haven't bothered me one bit like others said simply headspace off the shoulder and forget the belt is there. It may just be psychological but I feel I can safely push the heavier based belted cartridges a bit more than a non-belted. I've seen non-belted cases bulge in that very area in some sloppy chambered rifles but not on any of the belted Mags I've loaded for.

 

[Truc]

Adjusting the die can be done but it is quicker to use a shim, not sure if I have ever seen anyone in Benchrest adjust by using the shell holders.
When I size a case I do it just enough to close the bolt without the firing pin installed in the bolt. You will actually feel the case just a tiny bit. Newer brass won't need to be bumped, but when you fire it 5-6 times in a day over several days of shooting and shooting at the pressures that most shoot at, sometime during the match you will need to change the amount that the shoulder is bumped. By removing a 10/1000 shim and installing a 9/1000 shim or smaller is more precise and easier than other ways. I just saw that the company that sells the die to resize belted cases also sells shims. I use them in competition and also on my 7 SAUM and others as needed.
When hunting you may want to resize a bit more just to make sure that if dirt gets in there it will still function.

 

[Timber338]

Is there any bonus to using the longer shell holders vs just adjusting the depth of the FL die? I assume the shell holders make it easier and more reliable to make a .002" adjustment but I've always simply sized the case a little bit more until the cases will just chamber then lock down my die and forget about it. Belts haven't bothered me one bit like others said simply headspace off the shoulder and forget the belt is there. It may just be psychological but I feel I can safely push the heavier based belted cartridges a bit more than a non-belted. I've seen non-belted cases bulge in that very area in some sloppy chambered rifles but not on any of the belted Mags I've loaded for.

I think there is a definite bonus to using the Redding Competition Shellholders over just adjusting the depth of the FL die. When you are only adjusting the depth of the die, the standard shellholder is not contacting the base of the die. With the variables present in the press resizing operation such as more/less case lube, more/less speed/force on the press handle, that air gap between the die and the shellholder is going to allow the entire system to flex more. Finite element modeling shows that this air gap can introduce quite a bit of variation in shoulder bump from case to case. When you use the Redding shellholders, the top of the shellholder always contacts the base of the die and you reduce the variation down to .002" for any case you resize. Which is also why the Redding Comp Shellholders are made in .002" increments. Using shims is basically doing the same thing, but in my opinion the shellholders are a much cleaner solution to the problem. ML McPherson wrote a great article on this I think called 'what happens to a case when it is resized'. I just did a quick google search but could not find it. Great read if you can find it.

 

[Buttermilk]

I've never had an issue with any belted magnum case.

I treat them as if they don't have a belt. Head space on the shoulder.

I've owned two Rem 700 7RM rifles, one T/C Encore rifle 7RM, one T/C Encore handgun 7RM, one Browning A-bolt II 7RM, and also currently have a 30-338 WM.

None of these have ever given me any issues with the belt.

 

[MagnumManiac]

Quote, What I do now is use Redding Competition Shellholders that allow you to bump the shoulder back .001 to .002 inches smaller than the chamber. This effectively eliminates headspacing off of the belt. If I were to run across any brass that is hard to chamber, I would just throw it away. But right now using Nosler brass I have not had a single issue through several different batches of brass for both 300 win mag and 338 win mag.

There is another way to accomplish this and that is to use shims under the die, the shims start at .003" and go up to .010". You set the die to size too much then install the shims between the die and the press. This is common in shooting Benchrest as new brass needs less sizing than older brass.

This method does have some merit, BUT only with Redding dies that are designed to just touch the shell holder, not cam over like RCBS dies, for example.
I actually measure my head to shoulder dimensions between fired and unfired brass, then size to suit, no need for shims or comp shell holders. I have only ever had to use a shim when sizing a case to determine how much to remove from the top of a RCBS #4 shell holder because my 375 Weatherby chamber is .002" shorter than the minimum dimension and my Redding 375 Weatherby dies could not bump the shoulder ENOUGH for the case to chamber. This shell holder stays with the die set.
Hope this makes sense.

Cheers?
gun)
If you adjust your dies so that a sized case chambers with a slight feel, another 1/32 of a turn will give a .002"-.003" of headspace clearance.

 

[davkrat]

Cheers?
gun)
If you adjust your dies so that a sized case chambers with a slight feel, another 1/32 of a turn will give a .002"-.003" of headspace clearance.

That's the way I've always done it.

 

[MudRunner2005]

This is why I only neck-size belted mags. I neck-size for 3-5 firings, depending on when the bolt extraction gets a little stiff, then I FL size them once to get them back to get the body width back to spec. Then continue to neck-size, then repeat with the FL sizer.

 

[trazman]

I am also reloading quite a few years now the .300wm and I havent had a single problem. I use RWS brass and I push it to the max. I neck size until I feel some force to close the bolt and than I full size. Never had any problems, but RWS is really good brass maybe other brands would make more problems or less need for more FL sizeing...