Should FL dies be screwed in to touch the shell plate?

[stvo6mm]

Hi there.

I've read numerous articles on bumping and setting headspace etc.. I figure that when the manuafcturer and many replies here recommend screwing you FL die in to touch the shell plate this will only result in a case sized to a dimension set at the factory. There for I should not be screwing mine in that deep in order to achive a case length that suites the chamber of my rifle?

I am using Lee dies in an Lyman Crusher press.

 

[fdshuster]

stvo6mm: The factory "advice" to screw the sizer die down 'til it touch's the shell holder ( then, some say to back it off a "bit"), is a one size-fits-all method to give a better guarantee that the reload will fit in any of the thousands (?) of similar chambers out there.

They ( the factory) could care less if you are over-sizing your brass which will result in shorter usable case life, and maybe a little less accuracy.

You can adjust your sizer die to a more precise dimension by taking an as-fired case and attempting to rechamber it. You probably will not be able to close the bolt, or if it does close, it will be tight, with a lot of resistance. Start with the sizer lock ring adjusted a couple of turns above touching the SH, size, and again try to chamber. Keep doing that, by trial and error until the bolt closes normally on that case. Lock the die lock ring down so it cannot move & that's the proper adjustment for your chamber. If I were doing it, I'd lower the die body about a quarter turn in the lock ring, try to chamber, still tight, lower, etc. etc. When you reach the point that the bolt will close, but still with more than usual resistance, then lower the die body approx. 1/8 of a turn, 'til it closes normally. I like just a little resistance when I close the bolt. That tells me the case is locked up tight in the chamber with minimal slop front to rear.

Or, go to this sites home page, click-on "technical articles", scroll thru to the Stoney Point/ Hornady Chamber Over-all-Length gauge, read it and you may want to consider using this option.

Whichever method you use, be sure to keep your bolt locking lugs clean and well lubed with a light grease.

Adjusting the sizer die for your chamber's dimensions will result in much longer brass life ( depending on the cartridge & some other factors) and could also improve accuracy, impossible to say by how much.

 

[K31Scout]

Touching the shell holder normally bumps the shoulder back too far. Get a Hornady Headspace Gauge and unscrew the die until you are only bumping back .003 or .004

 

[matthias]

in my semi autos i touch the shell holder to the die. i do this so i make damn sure they will cycle.

for bolt guns i follow the advice above. for each rifle individually. so if i have two in the same caliber i have a die set for each. just easier that way.

 

[lurcher]

These days I do wind the die in till it touches the shell holder. I then use a set of redding competition shell holders which have a deck height that varies from 2 to ten thou, in two degree increments from a factory redding shell holder and use these to get 1-2 thou shoulder bump measured both with a gauge and in the chamber testing for fit with the bolt with firing pin assembly removed.

The reason I go with the die touching was that I read on here somewhere that if you are trying to only bump 1-2 thou and the die does not bottom out then different degrees of springback between different bits of brass may mean that you may wind up with more variation in the dimensions of the sized brass than if you bottom the die out. Can't argue against the fact that sizing without the die bottomed out still works though.

 

[steve4102]

Hi there.

I've read numerous articles on bumping and setting headspace etc.. I figure that when the manuafcturer and many replies here recommend screwing you FL die in to touch the shell plate this will only result in a case sized to a dimension set at the factory. There for I should not be screwing mine in that deep in order to achive a case length that suites the chamber of my rifle?

I am using Lee dies in an Lyman Crusher press.

You are using Lee dies, so you can use Lee instructions.

From Lee FL sizing die instructions.

Screw the full length sizer in until it touches the shell holder.
Then lower the ram and screw the die in 1/4 to 1/3 turn more.
Raise the ram and tighten the lock ring finger tight.

I have Lee, Redding, RCBS and Forster dies. The instructions for all of these say to touch the shell holder Plus 1/8 to 1/3 more. None of them say to just touch the shell holder.

If you want to set up your dies for .00X shoulder bump then purchase a Hornady/Stoney Point comparator and set them up exactly the way you want without guessing.

 

[Larryh128]

What FDSHUSTER said.

 

[Dgd6mm]

I like the Larry Willis gauge simply for knowing my shoulder bump measurement. With that being said, you can do it as Frank explaines and it will work everytime.

 

[KenO]

Hi there.

I've read numerous articles on bumping and setting headspace etc.. I figure that when the manuafcturer and many replies here recommend screwing you FL die in to touch the shell plate this will only result in a case sized to a dimension set at the factory. There for I should not be screwing mine in that deep in order to achive a case length that suites the chamber of my rifle?

I am using Lee dies in an Lyman Crusher press.

You are using Lee dies, so you can use Lee instructions.

From Lee FL sizing die instructions.

Screw the full length sizer in until it touches the shell holder.
Then lower the ram and screw the die in 1/4 to 1/3 turn more.
Raise the ram and tighten the lock ring finger tight.

I have Lee, Redding, RCBS and Forster dies. The instructions for all of these say to touch the shell holder Plus 1/8 to 1/3 more. None of them say to just touch the shell holder.

If you want to set up your dies for .00X shoulder bump then purchase a Hornady/Stoney Point comparator and set them up exactly the way you want without guessing.

Yep, read the instructions. I have the Stoney Point gauge and wasn't getting the shoulder bump with RCBS FL sizer. I called RCBS and the tech asked how I set it up. I told him I raised the ram and screwed the die in to touch. He said to lower the ram and screw it down another 1/4 turn, that I should get a "cam over" with the press when I re-size. Its in the instructions to do that.

Don't know what die maker says to just touch the die, or back off, I have most the colors of dies, and none of them say that.

That said, I use the gauge and screw it in or out to get the bump I want. Most the time its a very slight cam over, but it can depend on the shell holder brand also.

 

[pdog2225]

I cannot recall where I read it but when trying to improve my reloads I ran across an article on this. It said that the reason to lower the handle and screw the die in some is that it will tension the die threads and set the die up in line with the ram. I recall also that you should use something like feeler gauges or something solid between the die and shell holder if you need to. Because otherwise you may push the shoulder back to much.
I suppose you could try it both ways, then use a runout gauge and see if there is a differance.

 

[K22]

Acturally, most die manufacturer's instructions tell you to set the FL die flush against the shell holder and turn it an additional 1/8 turn. Most of the time this will result in oversizig your cases.

The better and I might add, the proper method to set up a FL die is to use a Wilson Case Gage to set your die so that you are not oversizing but sizing enough to assure trouble free chambering without over working the brass. This tool is very simple to use and proper headspace of a sized case can be readily determined.

More precise tools are available from Sinclair or Hornady to precisely measure shoulder bump to achieve a more precise sizing normally a .002 bump for bolt rifle but for hunting reloads, the Wilson Gage does a fine job.

I know some reloaders use the partial sizing method quite successfully and even some reloading manuals recommend it but I would avoid it since it can result in reloads that are difficult to chamber in the field. Go to riflemansjournal.blogspot.com and read the article by German Salazar regarding sizing cases for a detailed explanation of why neck sizing and partial sizing are not the best way to go.

 

[fdshuster]

ken orris: Guess you don't have any "green" Redding dies. An excerpt from their instruction sheet provided with one of my Redding die sets: "Normal reloading operations require the use of the resizing and decapping die first and this die is screwed into the 7/8 x 14 threaded hole of the reloading press to the point where it just contacts the shell holder of the press ram when it is in its uppermost position".

When I was using RCBS dies, ( have not bought them in many years now), they also included much the same instructions with their die sets.

Just one of the problems with this advice is that not all shellholders are created equal (thickness), even by the same manufacturer.

 

[jo191145]

No two chambers are the same,,welllll unless you make them the same,,,,, that is possible.
No two dies are the same. Therefor paying attention to any one size fits all directions is sheer madness.
Pay attention to your specific measurements. The emphasis being on pay attention. To your specific measurmwents that is.
The generic instructions should go in the trash.

Just my opinion but I believe the reason FL sizing got a bad rap and NS sizing became a fad lies mostly in those stupid one size fits all instructions the die manufacturers came up with. They're just fine if your sole requirement is making the gun go bang and hitting a pie plate at 100 yards three shots per year.

 

[fdshuster]

jo191145: And if I might add to your post: If you care about getting 2 or 3 reloads out of your brass before you get incipiant case head seperation.

 

[jo191145]

fd

absolutely correct, hence three shots per year ;D

 

[Zia Hunter]

For my bolt and single shot rifles, I set up the dies with fire formed brass to bump the shoulders approx. .002" or slightly less. I have used the Hornady, Innovative Technologies and RCBS Precision Mic to do this and they all work. I neck size brass for these rifles and only FL resize when necessary. I have noticed significant differences in headspace measurements between new brass and fire formed cases ranging from .007 to .015. Sizing according to the die instructions will almost always result in over sizing the case with the resulting shortening of life. More importantly, minimum resizing has resulted in greater accuracy and significantly so in some calibers. This is particularly the case for belted magnums. For setting up dies in my gas guns, the RCBS Precision Mic has proved the most useful. I use a Forster COAX press so cam over is not an issue.

 

[stvo6mm]

Thanks all for your responses on this. Agree that instructions do so to go past the touch point of die to shell holder. Same principle though of sizing case to a factory dimension by removing all clearance between die base and shell holder.

Interesting though regrading presses that cam over. Mine does though I'm unclear on the exact purpose of the cam? I originally though it was to provide a consistent top-dead-centre and hence repeatable pressure point for sizing and seating etc... but some of your replies have me rethinking that. Any thoughts?? Suspect you do. )

 

[wapiti25]

+ on what fdhuster said.

 

[243winxb]

I have found RCBS shell holder to be +/- .001" Standard is .125" Not so with shell plates. Each station may be different, requiring some kind of tool/gage to measure shoulder set back of bottle neck cartridges. This shell plate will cause case head/body seperations on firing the ammo.

 

[KenO]

ken orris: Guess you don't have any "green" Redding dies. An excerpt from their instruction sheet provided with one of my Redding die sets: "Normal reloading operations require the use of the resizing and decapping die first and this die is screwed into the 7/8 x 14 threaded hole of the reloading press to the point where it just contacts the shell holder of the press ram when it is in its uppermost position".

When I was using RCBS dies, ( have not bought them in many years now), they also included much the same instructions with their die sets.

Just one of the problems with this advice is that not all shellholders are created equal (thickness), even by the same manufacturer.

I agree, but I wouldn't think of setting up the die without gauges. As I mentioned also, shell holders make a big difference. Your right about Redding, my bushing dies say what you posted, I stand corrected. I should never say "all", I knew after I posted I would regret that, LOL.