Setting dies for a belted mag?

Steve O

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Jan 27, 2011
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8
I was told in order to get the most accuracy out of a belted mag to set your dies to head space off the shoulder and not the belt. How do I do this?
 
There are a couple of ways to do it. One would be to get a set of Redding competition shell holders. The other is to adjust your die to size just enough so that the case chambers easily.

I don't think head spacing off the shoulder is done so much to improve accuracy as it is to improve case life. The same principle applies, by the way, to bottlenecked rimmed cases.
 
There are a couple of ways to do it. One would be to get a set of Redding competition shell holders. The other is to adjust your die to size just enough so that the case chambers easily.

I don't think head spacing off the shoulder is done so much to improve accuracy as it is to improve case life. The same principle applies, by the way, to bottlenecked rimmed cases.

+1
I neck size only as long as it will chamber after the first firing.

Case life is improved and accuracy benefits from not full length sizing.

J E CUSTOM
 
+1
I neck size only as long as it will chamber after the first firing.

Case life is improved and accuracy benefits from not full length sizing.

J E CUSTOM

Got to strongly disagree, that is an old wives tail not backed up by facts for an across the board statement

The majority of the BR (both SR and LR) FL size based on surveys at Br central! They are after accuracy. So that really kills the NS is "the" superior for accuracy theory.

Properly sized dies that are adjusted correctly lead to better accuracy and case life.

NS is touted when people do not know how to adjust the dies, buy oversized dies, then NS and suddenly think it helps them. Yes compared to what they were doing, but not compared to proper dies and correctly setup to FL size.

NS and then body bump die is NOT NS, that is FL size, just done in two steps.

Specific example, world record 5 shot 1.4" group at 1k was shot with shortened 338 Lapua brass that was shot 54 times at time of record setting. Thrown away after 80th reloading. NO NS only brass has remotely every done that.

BH
 
Got to strongly disagree, that is an old wives tail not backed up by facts for an across the board statement

The majority of the BR (both SR and LR) FL size based on surveys at Br central! They are after accuracy. So that really kills the NS is "the" superior for accuracy theory.

Properly sized dies that are adjusted correctly lead to better accuracy and case life.

NS is touted when people do not know how to adjust the dies, buy oversized dies, then NS and suddenly think it helps them. Yes compared to what they were doing, but not compared to proper dies and correctly setup to FL size.

NS and then body bump die is NOT NS, that is FL size, just done in two steps.

Specific example, world record 5 shot 1.4" group at 1k was shot with shortened 338 Lapua brass that was shot 54 times at time of record setting. Thrown away after 80th reloading. NO NS only brass has remotely every done that.

BH

It doesn't matter if you agree with me or not !!!!!

I answered his question about a belted case . the 338 Lapua is Not belted !!!!!! (A belt is the ring
at the rear of the case body that the round head spaces on). Just incase you don't know that.

I don't know why you dont like Neck sizing But that is your choice and as far as how I size brass
I think after over 50 years of reloading I do know how to reload. and I do know how to set
any die properly.

We can debate how many more loadings you can get than me but that does not help the guy
that ask the question. If you would spend more time trying to help those that ask for help
instead of finding fault with everyone that you don't agree with it would be productive.

Post your opinion and let the poster decide. Yours is not the only way to do something.

Besides how many benchresters use belted cases ?

Stick to the questions and refrain from the character assassination and we will do fine, I respect
your opinion but this is of no help to the man that ask for help.

Enough said .

Sorry Steve O. and Len.

J E CUSTOM
 
As JE very correctly suggests, neither neck sizing nor full length sizing iof themselves offer any magic or certain results for either accuracy or case life.

The effect on case life depends entirely on the specific diameter dimensions of the individual's chamber and size die chamber. If a the body of a FL die is largish and the chamber is smallish then FL sized cases won't be excessively worked and splits will be delayed.

So far as the case's neck or type of die goes, if necks get worked more than the body, the necks will split sooner than the bodies. No great puzzle about that is there? And just how much it gets worked is, again, dependant on the actual diameters of the die and chamber necks. Conventional dies, any type, normally sizes necks down a lot more than would be best and then get expanded back up.

On average, conventional neck sizers work the necks as much as conventional FL dies so there is no certainty that neck sizing will increase case life. Bushing neck dies, used correctly, can work necks less but we have to fiddle with finding the exact diameter bushing and that's a PITA as well as costly. I MUCH prefer using Lee's inexpensive Collet Neck Sizer, it obtains the best neck internal diameter without concern about how thick the necks are and it works the neck the absolute minimum to do it. The Lee neck die used with a body die is the best of all possible combonations, IMHO.

Accuracy is often equal no matter the sizing method. The only way for anyone to KNOW which, if either, method works best in his rifle is to try both ways.

I strongly suspect the record breaking 80 times fired case mentioned above was "FL sized" in a cusom made die, not a store bought one, and the chamber probably only had maybe a thou of clearance for the loaded cartridge. Neither of those conditions are normal so the results aren't normal and therefore it means nothing to us.
 
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As JE very correctly suggests, neither neck sizing nor full length sizing iof themselves offer any magic or certain results for either accuracy or case life.

The effect on case life depends entirely on the specific diameter dimensions of the individual's chamber and size die chamber. If a the body of a FL die is largish and the chamber is smallish then FL sized cases won't be excessively worked and splits will be delayed.

So far as the case's neck or type of die goes, if necks get worked more than the body, the necks will split sooner than the bodies. No great puzzle about that is there? And just how much it gets worked is, again, dependant on the actual diameters of the die and chamber necks. Conventional dies, any type, normally sizes necks down a lot more than would be best and then get expanded back up.

On average, conventional neck sizers work the necks as much as conventional FL dies so there is no certainty that neck sizing will increase case life. Bushing neck dies, used correctly, can work necks less but we have to fiddle with finding the exact diameter bushing and that's a PITA as well as costly. I MUCH prefer using Lee's inexpensive Collet Neck Sizer, it obtains the best neck internal diameter without concern about how thick the necks are and it works the neck the absolute minimum to do it. The Lee neck die used with a body die is the best of all possible combonations, IMHO.

Accuracy is often equal no matter the sizing method. The only way for anyone to KNOW which, if either, method works best in his rifle is to try both ways.

I strongly suspect the record breaking 80 times fired case mentioned above was "FL sized" in a cusom made die, not a store bought one, and the chamber probably only had maybe a thou of clearance for the loaded cartridge. Neither of those conditions are normal so the results aren't normal and therefore it means nothing to us.
I agree. I do both. my 7mm rem mag likes FLS. MY 22-250 is abit fussy. Nosler 50 gr bt loves NS. The 50 gr Barnes likes FLS. The thing about hand loading is to experiment. Take all info from on line with a grain of salt and do not bash another persons findings. I have said it before, follow the book and grow from there. set your dies to what the maker says and go from there.
 
JE

Well I certainly do not have 50 years of reloading, (only 45) but 25 years ago I learned something, that you must have missed, so here is a news flash.

FYI belted cases are used all the time in LR BR (7mm Mag, 300 Win Mag, 300 & 340 Wthby and derivatives for example) and they are set up to FL size and headspace off the shoulder not the belt as some think you must do.

Obviously you did not know that based on what you said, so I can see your confusion and why you think it is personal.

Well only one belted case is designed to headspace off the belt and that is the original H&H case, all other belted cases leave .020-.030 of gap from the case to the chamber shoulder for the initial firing and if you resize based on headspacing off the belt, the case will often separate in about 3-4 firings.

Custom honed FL bushing die costs $80 from JLC precision if it is a caliber that has a redding body die ($27).

So I fail to to see the valid arguement that someone can have a $1500-4000 rifle, $500-2000 scope and somehow we feel the need to say you must NS only because that is the best way to get a chamber fit, when better dies are out there (even for factory chambers) that will not work the brass as much, fit tighter and basically proven by the guys that live for extreme accuracy to be the better method.

A case that has only .001 or so of pushback and will chamber every time; and will be as tight in that chamber as possible . Admittedly a min variance reamer and matching die is the absolute best of both worlds, but not necessary. With belted magnum cases that are FL sized with a fitted die going 20-30 firings on a routine basis, works better than NS only and throw away when the bolt locks or does not chamber. I have over 30 firings on a 300 wthby and 300 Baer FL sizing and you never see anyone saying that NS only will do that.

Boomtubes Lee Collet and a body die still equals FL sizing also, just two steps. That point is often not stated by someone touting NS, but when you dig down you find that they have discovered that they have to do it.

Sinclair Intl tech reps just posted a great article on setting up FL dies and NS only today on 6mmBR. http://bulletin.accurateshooter.com...g-die-set-up-tip-from-sinclair-international/

Also, FYI it is not a personal attack and not personal!

BH
 
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JE

Well I certainly do not have 50 years of reloading, (only 45) but 25 years ago I learned something, that you must have missed, so here is a news flash.

FYI belted cases are used all the time in LR BR (7mm Mag, 300 Win Mag, 300 & 340 Wthby and derivatives for example) and they are set up to FL size and headspace off the shoulder not the belt as some think you must do.

Obviously you did not know that based on what you said, so I can see your confusion and why you think it is personal.

Well only one belted case is designed to headspace off the belt and that is the original H&H case, all other belted cases leave .020-.030 of gap from the case to the chamber shoulder for the initial firing and if you resize based on headspacing off the belt, the case will often separate in about 3-4 firings.

Custom honed FL bushing die costs $80 from JLC precision if it is a caliber that has a redding body die ($27).

So I fail to to see the valid argument that someone can have a $1500-4000 rifle, $500-2000 scope and somehow we feel the need to say you must NS only because that is the best way to get a chamber fit, when better dies are out there (even for factory chambers) that will not work the brass as much, fit tighter and basically proven by the guys that live for extreme accuracy to be the better method.

A case that has only .001 or so of push back and will chamber every time; and will be as tight in that chamber as possible . Admittedly a min variance reamer and matching die is the absolute best of both worlds, but not necessary. With belted magnum cases that are FL sized with a fitted die going 20-30 firings on a routine basis, works better than NS only and throw away when the bolt locks or does not chamber. I have over 30 firings on a 300 wthby and 300 Baer FL sizing and you never see anyone saying that NS only will do that.

Boomtubes Lee Collet and a body die still equals FL sizing also, just two steps. That point is often not stated by someone touting NS, but when you dig down you find that they have discovered that they have to do it.

Sinclair Intl tech reps just posted a great article on setting up FL dies and NS only today on 6mmBR. Full-Length Sizing Die Set-Up — Tip from Sinclair International « Daily Bulletin

Also, FYI it is not a personal attack and not personal!

BH

Thanks BH
It sounded personal because you did not disagree, you just quoted me and then attacked
everything I said.

And for what it is worth "EVERY" belted case Is designed to head space off the Belt or they
wouldn't have one.

The fact that some re loaders chose not to use the belt is not the issue the question of how
to headspace off the shoulder with a belted case is just a simple matter of fire forming and then
Not moving the sholder or changing the body size to maintain case size and capacity so the case is not pushed forward until it touches the belt by the bolt.

Once fired, the fired case has "No" head space and It moves the belt away from the chamber and seats against the shoulder.

And you are right there are a few belted cases used by bench rest shooters but the majority
of the cases used are beltless cases that headspace against the shoulder.

I think it is great that you can get 30 + firings out of a 300 Weatherby and I would like to have
some of that brass you are using. (I only get 5 or 6 with annealing) and then the primer pockets
are gone.

If I loaded a mag down enough to get that many loadings it would not be called a magnum.
and would be called a 300 slow poke or something.

I will not quote any more of your post because I don't believe it's productive, But I will post my opinion.

So have a good day.

J E CUSTOM
 
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I just sized some unfired Win. brass for my 7mm Rem Mag. I have the Forster benchrest die set. I followed the enclosed instructions when setting up my dies. I put the ram in the full upright position, threaded the sizing die down until it touched the shellholder and then locked it in place and sized my cases. Did I do it correctly? If not, then what should I do next time. Thanks in advance for the info.
 
I am surprised no one has suggested using a comparator to measure the shoulders of cases before firing and then after firing and using the measurements as a means to setting resizing die length.
 
I am surprised no one has suggested using a comparator to measure the shoulders of cases before firing and then after firing and using the measurements as a means to setting resizing die length.


Geeze Louise!!! lightbulblightbulb Great idea I had never thought of that.

Thanks!!

Jeff
 
And for what it is worth "EVERY" belted case Is designed to head space off the Belt or they wouldn't have one.

J E CUSTOM

JE

the belt came in early on with the 300 H&H and I forgot the 375 H&H and was needed due to the steep shoulder angle of that case, where the firing pin drove the case off the bolt face due to the really shallow shoulder angle. It was also thought to aid feeding. That is no longer the case that is "needed" with the sharper shoulder magnums, except for the original 300 H&H which still needs the belt. They are totally worthless at this point in time and confusing to people obviously

the fact that there is a belt does not mean it is needed except in factory chambers with factory loads due to the long gap they leave between the end of the case and shoulder. After initial firing you absolutely DO NOT want to resize to headspace off the belt or you will get case separation in a few firings.

I do not load powder puff loads either, so do not think that is the issue. It is proper dies, FL sizing and correct adjustment. As for you case life issue, primer pockets is a classic indicator of over pressure problems, not a sizing issue.

FWIW, the BR shooters set up all the magnums to headspace off the shoulder also when chambering, not the belt and resize off the shoulder.

The fact that I disagree with what you said does not make it personal to you, only the info.

BH
 
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